General Science Pointers PDF

Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. GENERAL SCIENCE POINTERS BASIC CONCEPTS AND LAWS Science and Technology Science - is a systematic study that is concerned with facts and principles, and methods that could be observed in our natural or physical and social environment. It comes from the Latin word 'scire' that means 'to know’. - is both a body of knowledge and a process – away of thinking, a way of solving problems The Branches of Science THE PHYSICAL SCIENCES Physics: The study of matter and energy and the interactions between them. Physicists study such subjects as gravity, light, and time. Albert Einstein, a famous physicist, developed the Theory of Relativity. Chemistry: The science that deals with the composition, properties, reactions, and the structure of matter. The chemist Louis Pasteur, for example, discovered pasteurization, which is the process of heating liquids such as milk and orange juice to kill harmful germs. Astronomy: The study of the universe beyond the Earth's atmosphere. THE EARTH SCIENCES Geology: The science of the origin, history, and structure of the Earth, and the physical, chemical, and biological changes that it has experienced or is experiencing. Oceanography: The exploration and study of the ocean. Paleontology: The science of the forms of life that existed in prehistoric or geologic periods. Meteorology: The science that deals with the atmosphere and its phenomena, such as weather and climate. THE LIFE SCIENCES (BIOLOGY) Science I -1- Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Botany: The study of plants. Zoology: The science that covers animals and animal life. Genetics: The study of heredity. Medicine: The science of diagnosing, treating, and preventing illness, disease, and injury. Scientific Method is the logical method used by scientists to acquire knowledge that is used to explain different phenomena in nature. A thing observed by the senses is called a phenomenon; a scientifically tested observation is called a fact. The scientific method has six basic steps, namely: a. Identify and clearly state the problem. Questions arise from something observed as unusual; problem that is specific, measurable, and attainable is identified. b. Gather information pertinent to the problem. This is done by recalling past experiences concerning the problem, interviewing people who are knowledgeable of the problem, and researching in libraries and research centers. c. Formulate hypothesis. Based on information or data gathered, an 'educated guess' can be made. d. Test the hypothesis. Carrying out experiments. Controlled experiment - manipulating one of the conditions or factors that may affect the result of experiment. 1) Trials - number of times experiment is repeated. 2) Controls - factors that are kept constant throughout the experiment 3) Variables - factors that change during the experiment. Kinds: 1. Independent or experimental - factors that are changed. Science I -2- Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. 2. Dependent - factors that change as a result of changes in the independent variable. Presentation of Data Tables - easy to read, organized presentations. Graphs - readily show patterns of data. Kinds: 1. Line - proper to use when comparing two continuously changing variables. 2. Bar - appropriate to use when comparing a changing value with an unchanging value. e. Draw a generalization or conclusion. Conclusion - a statement about the result of the experiment. Law - a statement which describes what happens but does not explain the cause of the occurrence. Theory - hypothesis that can be explained from observations. f. Apply the principle (conclusion) to other situations. Scientific Traits Scientific knowledge may also be obtained through the use of models and ideas, or through serendipity or accidental discovery. In scientific study,.some standards or procedures must be observed. Scientists should always exhibit scientific attitudes like the following: a. Curiosity - keen observation of things and events in the surroundings. Galileo's intensive desire to study heavenly bodies drove him to use a telescope to study the moon, the planets, the sun, and the stars. b. Logic and system - use of step-by-step experimental method and keeping of accurate records. Science I -3- Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Gregor Mendel was successful in his study of hereditary traits because he used logical experimental methods and accurately recorded his observations. c. Open-mindedness - readiness or willingness to change or modify ideas or principles when necessary. Johannes Kepler changed his notion about the popular belief during his time that the planets moved along perfect circles to a more accurate information that these follow elliptical orbits. d. Intellectually honest - -acknowledging contribution of others to one's success. Isaac Newton recognized the role of Galileo and others in his formulation the Laws of Motion. e. Hardwork and perseverance Marie Curie and his husband Pierre had to work on several thousand kilograms of uranium ore to strain a tenth of a gram of pure uranium. f. Not opinionated – using hard evidences to prove ones theory. John Dalton used experimental evidences to support his atomic theory. g. Creativity and critical thinking Albert Einstein did not just depend on established facts and accepted beliefs during his days. Rather, he used these to develop his own theory in different perspective. Technology is defined as the application of scientific knowledge to practical purposes. In short, it is an applied science. It is classified into three kinds, namely: a. Machines - include tools, gadgets or devices that help us do our activities faster and better. They make life more pleasant to us to do certain things which we normally cannot do. (e.g., airplane, internet, CT scan. and computers.) b. Products - materials produced or made through artificial or natural means. They make life more pleasant, more convenient, and more comfortable. (e.g., steel, toothpaste, chemical fertilizers, and pesticides) c. Processes - include the ways of doing things. (e.g., food Preservation, prawn culture and induced fruiting.) Science I -4- Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Measurement International System (SI) of Measurement Measurement is the process of comparing a quantity with a chosen standard. The International System (SI) is the system of units that scientists have agreed upon and is legally enforced in almost all parts of the world. There are seven basic quantities in this system: Quantity Unit Length Meters (m) Mass Kilograms (kg) Time Seconds (s) Electric current Amperes (amp) Temperature Kelvin (K) Amount of substance Moles Luminous intensity / light Candelas Two factors affect the degree of measurements. They are (a.) the ability to use the measuring instruments properly and (b.) the precision of the instrument. The unit factor method is a systematic technique for solving numerical problems. The factors are derived from fixed relationships between quantities. The main purpose is to cancel units not desired using fixed relationships, leaving behind the unit desired. Units of a derived quantity like density may be inverted to be able to cancel the unit not desired. Metric Prefixes Metric prefixes are pretty easy to understand and very handy for metric conversions. You don't have to know the nature of a unit to convert, for example, from kilo-unit to mega-unit. All metric prefixes are powers of 10. Prexis Symbol Factor giga G 109 = 1,000,000,000 mega M 106 = 1,000,000 kilo k 103 = 1,000 hecto h 102 = 100 Science I -5- Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. deka da 101 = 10 deci d 10-1 = 0.1 centi c 10-2 = 0.01 milli m 10-3 = 0.001 micro µ 10-6 = 0.000,001 nano n 10-9 = 0.000,000,001 pico p 10-12 = 0,000,000,000,001 Most people even in the countries where metric system is used only know the most important metric prefixes like 'kilo' and 'milli'. They are very handy for understanding metric conversions. Temperature There are three temperature scales in use today, Fahrenheit, Celsius and Kelvin. Fahrenheit temperature is a scale based on 32 for the freezing point of water and 212 for the boiling point of water, the interval between the two being divided into 180 parts. The conversion formula for a temperature that is expressed on the Celsius (C) scale to its Fahrenheit (F) representation is: F = 9/5C + 32. Celsius temperature scale also called centigrade temperature scale, is the scale based on 0 for the freezing point of water and 100 for the boiling point of water. Invented in 1742 by the Swedish astronomer Anders Celsius, it is sometimes called the centigrade scale because of the 100-degree interval between the defined points. The following formula can be used to convert a temperature from its representation on the Fahrenheit ( F) scale to the Celsius (C) value: C = 5/9(F - 32). The Celsius scale is in general use wherever metric units have become accepted, and it is used in scientific work everywhere. Kelvin temperature scale is the base unit of thermodynamic temperature measurement in the International System (SI) of measurement. It is defined as 1/ 273.16 of the triple point (equilibrium among the solid, liquid, and gaseous phases) of pure water. The Kelvin (symbol K without the degree sign) is also the fundamental unit of the Kelvin scale, an absolute temperature scale named for the British physicist William Thomson, Baron Kelvin. The Kelvin scale is related to the Celsius scale. The difference between the freezing and boiling points of water is 100 degrees in each, so that the Kelvin has the same magnitude as the degree Celsius. To convert Celsius to Kelvin: K = __°C + 273 Volume Science I -6- Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Volume refers to the amount of space that an object occupies. It is often used to signify more accurate measurements. 2 cm VOLUME OF A REGULAR SOLID 2 A regular solid is one having length, width, and thickness or height and each can be measured in a cm of measurement which is the meter. single straight line. Tomeasure the volume, we use a standard unit The volume of a regular solid is obtained by multiplying its length, width and thickness. The volume is expressed in cubic units ( ex. Cubic meter, cubic cm, etc) VOLUME OF A LIQUID Liquid volume is also measured in cubic meters but the use of liter (L) is widely accepted. Graduated cylinder is used to measure the volume of liquid. In reading the measurement of the volume of clear liquid, read the lower meniscus. For colored liquids, read the upper meniscus. Liquid Volume Equivalents 1dm3 = 1liter (L) Application: 1 cm3 = a milliliter (mL) VOLUME OF AN IRREGULAR SOLID 1000 cm3 = 1liter 2 cm An irregular solid is one where a dimension cannot be measured in a single straight line. The displacement method is used to determine the volume of irregular solids. Displacement method used Calculate the volume of the block of wood. by Archimedes: Fill a container with Given : Solution: water, put the object in the container L = 2 cm Volume = L x W x T and catch the overflow. Get the W= 2 cm = 8 cm3 volume of the overflow) T= 2 cm Science I -7- Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Application: A cylinder contains 25.9 mL of water. When a small rock is placed in it, the water rises to 34.7 mL. What is the volume of the rock? Given: Solution: V1 = 25.9 mL Vrock = 34.7 mL – 25.9 mL V2 = 34.7 mL = 8.8 mL Density Density is the mass of the object per unit volume. Substances differ in their densities. Each substance has a specific density. All materials with a density les than 1 g./cc (density of water) will float on water, and all those with density greater than 1 g/cc will sink. D= Mass / Volume (g/cc) Application: The volume of an object weighing 2.5 g is 1.4 cc. Will the object float or sink on water Given : V = 1.4 cc M= 2.5 g Solution: D = M/ V = 2.5 g / 1.4 cc = 1.79 g/cc Answer: the object will sink since it is denser than water. (Density of water = 1 g/cc) Science I -8- Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Force - normally refers to the measurement of a push or a pull - anything that changes the speed and direction of moving objects or that which causes a stationary object to start moving in a straight line MEASURING FORCE Gravitational force is the pull that the earth exerts on all objects and is measured by the weight of an object. Some instruments for measuring weight are : the bathroom scale and the balance (or kilohan) you often see in the market. TYPES OF FORCES Gravitational force – downward force that the earth exerts on objects a. Inertia – tendency of an object to remain at rest or maintain its motion unless disturbed by a force b. Friction- resists / opposes the relative sliding movement of two surfaces in contact with one another. c. Centripetal force – drive a thing inward toward a center or rotation. It keeps an object moving in a circular path. d. Force of Gravity – that which is acting on an object which enables it to exert an equal and opposite force on its support. Nuclear Force- the strongest known force which holds together the protons and neutrons in the nucleus of an atom. Electromagnetic Force- binds electrons to the atomic nucleus, atoms in the molecules, ions in solid matter, and molecules into iquids and solids. MASS vs WEIGHT Mass indicates the quantity of matter in a material object. It does not change, thus it a property that is constant. It is measured in a unit called kilogram. Weight on the other hand, is th measure of the pull of gravity on an object. On earth, it depends on the mass of the object and its distance from the venter of the earth. The greater the mass of an object, the greater is its weight. The closer is to the center of the earth, the greater is its weight. Weight is expressed in N unit. 100g = 1N. Science I -9- Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Work In science, work is done only when the force applied to an object actually moves the object in the direction of the force. This is represented as: WORK = force x displacement Force- anything that causes motion or a change in motion Displacement – the distance and direction through hich an object is moved CALCULATING THE AMOUNT OF WORK W = F x d (Newton) ( meter) = Newton-meter or joule Application: How much work do you do by pushing a sack of rice with a force of 50 N across a distance of 10 meters? Given: F= 50 N D = 10 m Solution: W= F x d = 50 N x 10 m = 500 Nm or 500 J * note : 100 g = 1 N Machines Machine is any mechanical device that we use yo help us do our work, or make our work easier Simple Machines – machines that have only one or two parts Compound Machines – machines that make use of or more simple machines Science I - 10 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. SIMPLE MACHINES a. Lever – any rigid body which is pivoted about a point called fulcrum (e.g. crowbar, hammer, pliers, nutcracker, tongs, table knife, baseball bat) b. Pulley- a wheel with a grooved rim over which a rope passes.( as in flag pole) c. Wheel and axle – consists of a wheel attached to an axle so that if you push on the wheel, the axle turns also ( e.g. doorknob, eggbeater, screw driver) d. Inclined plane –a flat surface with one and higher than the other. The longer it is in relation to its height, the larger is its mechanical advantage (e.g. plank, ladder, winding road) e. Wedge – an inclined plane with either one or two sloping sides. The smaller the angle of the wedge,the greater the mechanical advantage ( nail,scissors, chisel, knife) f. Screw – spiral inclined planes.Works by transferring force exerted on the circumference of the screw (food grinder, metal screws) Energy The term energy is derived from the Greek word, energeial (en meaning in and ergon , meaning work). Anything that is able to do work possess energy. Energy is the ability to do work or the ability to exert force on an object and make it move. FORMS OF ENERGY a. Mechanical Energy kinetic energy – energy possessed by an object or a body in motion potential energy- energy possessed by a body because of its position or state b. Internal Energy or Thermal Energy – total energy coming from the attractive and repulsive forces of all the particles or molecules in a body c. Heat Energy – energy which flows from one body to another due to a temperature difference between them, and the flow is always from the hotter to the colder body d. Electrical Energy – electricity is the energy of electrons flowing through conductors, like copper wires and aluminum wires. e. Chemical Energy – energy stored in matter due to forces of attraction and to the arrangement of subatomic particles in atoms and of atoms in the molecules of substances. f. Radiant Energy – energy of the electromagnetic waves , radio waves, infrared rays, visible light, ultraviolet rays, x rays and gamma rays. g. Nuclear Energy – energy released from nuclear fusion or fission of atomic nuclei of heavy element or light element. METHODS OF HEAT TRANSFER Science I - 11 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Conduction The molecules in a material are always moving. When one part of a material is heated, the molecules in that part move faster and collide with other molecules. As this goes on, heat is conducted from molecule to molecule until the heat is spread throughout the material. This is conduction. A conductor is the material through which heat passes easily. An insulator is a material that conducts heat poorly. Convection The movement of a gas or liquid brought about by temperature differences creates a convection current. Heat is transferred by Convection when a gas or liquid moves from one place to another. Radiation Heat transfer when heat is given of in all directions around them is radiation. The sun and other hot objects radiates energy. ENERGY RESOURCES a. Fossil Fuels 1. Coal – being mined formed from trees and other vegetation buried in swamps crated by the encroaching sea 2. Petroleum - a liquid mixture of gaseous liquid and solid hydrocarbons. 3. Natural Gas- composed entirely of carbon and hydrogen. It is 50 to 94% methane and other hydrocarbons. 4. b. Hydroelectric Power Hydroelectric power pertains to the production of electricity by means of generators driven by water turbines. c. Geothermal Energy - Thermal energy inside the earth, energy of steam from beneath the earth’s surface d. Wind Energy- energy harnessed through the windmill e. Solar Energy- energy from the sun, radiant energy. The visible light is harnessed to produce the electricity by means of so-called solar cells or photovoltaic cells, which generate eletricity when exposed to sunlight Earth Formation of the Earth BIG BANG Science I - 12 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. In the beginning there is only a super-massive gaseous point in our empty universe. Instantaneously and randomly, enough energy is created to break the gravitational bond holding this massive body together, exploding the super-heated particles throughout space. In less than one millionth of a second, protons, neutrons, electrons, and their anti-particles begin to form. As time moves on, particles begin to cool by giving off energy, which allows them to combine to create the first and most simple ion, hydrogen, as well as a few more massive atoms. More time passes; the atoms are becoming more abundant in the universe. They begin to pull together through atomic forces and the gravitational force. Gaseous bodies become more massive, attracting more atoms and becoming more massive. The gravitational force of these early bodies is so great that they collapse in on themselves, beginning fusion. Hydrogen atoms combine, yielding larger atoms and enormous amounts of energy; enough energy to keep these stars from collapsing. Eventually, the fusion process has to end and the star will explode, sending out more massive atoms into the universe. Over time, these atoms collect and combine to create planets, smaller stars, asteroids, and numerous other solid bodies. FORMATION OF SOLAR SYSTEM As matter began to condense and stars began to form, one such star appeared where the Sun now appears within the Milky Way Galaxy. After igniting with fusion and burning its usable hydrogen and other larger elements, the star exploded, sending matter out in all directions. Once again, through gravitational forces, this matter eventually cooled and collected in a few key areas, forming the planets and the asteroid belt. The asteroid belt is simply an early form of the collection of matter that was not able to completely form a planet due to Jupiter's gravity. Some early planets may have collided with other early planets, creating larger planets, moons, or possibly space rocks. In the meantime, a smaller star began to form at the center of the previous explosion and our Sun started its fusion process again. Earth’s Structure The earth consists of several layers. The three main layers are the core, the mantle and the crust. The core is the inner part of the earth, the crust is the outer part and between them is the mantle. The earth is surrounded by the atmosphere. Till this moment it hasn't been possible to take a look inside the earth because the current technology doesn't allow it. Therefore all kinds of research had to be done to find which material the earth consists, what different layers there are and which influence those have (had) on the earth's surface. This research is called seismology. Science I - 13 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. THE CORE - The inner part of the earth is the core. This part of the earth is about 1,800 miles (2,900 km) below the earth's surface. The core is a dense ball of the elements iron and nickel. It is divided into two layers, the inner core and the outer core. The inner core - the center of earth - is solid and about 780 miles (1,250 km) thick. The outer core is so hot that the metal is always molten, but the inner core pressures are so great that it cannot melt, even though temperatures there reach 6700ºF (3700ºC). The outer core is about 1370 miles (2,200 km) thick. Because the earth rotates, the outer core spins around the inner core and that causes the earth's magnetism THE MANTLE - The layer above the core is the mantle. It begins about 6 miles (10 km) below the oceanic crust and about 19 miles (30 km) below the continental crust (see The Crust). The mantle is to divide into the inner mantle and the outer mantle. It is about 1,800 miles (2,900 km) thick and makes up nearly 80 percent of the Earth's total volume. THE CRUST - The crust lies above the mantle and is the earth's hard outer shell, the surface on which we are living. In relation with the other layers the crust is much thinner. It floats upon the softer, denser mantle. The crust is made up of solid material but these material is not everywhere the same. There is an Oceanic crust and a Continental crust. The first one is about 4-7 miles (6-11 km) thick and consists of heavy rocks, like basalt. The Continental crust is thicker than the Oceanic crust, about 19 miles (30 km) thick. It is mainly made up of light material, like granite. Plate Tectonics Science I - 14 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. The earth's crust consists of a number of moving pieces or plates that are always colliding or pulling apart. The Lithosphere consists of nine large plates and twelve smaller ones. The continents are imbedded in continental plates; the oceanic plates make up much of the sea floor. The study of Tectonic plates - called plate tectonics - helps to explain continental drift, the spreading of the sea floor, volcanic eruptions and how mountains are formed. The force that causes the movement of the tectonic plates may be the slow churning of the mantle beneath them. Mantle rock is constantly moved upwards to the surface by the high temperatures below and then sinks by cooling. This cycle takes millions of years. Continental drift The drift of the plates across the surface of the earth has been going on over millions of years, which still changes the outward appearance of the earth. When you look at the map of the world, you see how well the east coast of North and South America fits into the west coast of Europe and Africa. Over millions of years these continents have slowly drifted apart. (continental drift). Diverging plates Where plates pull apart, hot molten rock (fluid magma) emerges as lava and so new matter is added to the plates. In this way new oceanic plates are formed. The place where this happens is known as a mid-ocean ridge. Mid-ocean ridges are rarely more than about 4,920 ft. (1,500 m) high, but they may snake along the ocean bed for thousands of miles. Beneath each of the world's great oceans there is a mid-ocean ridge. An example is the Mid-Atlantic Ridge in the Atlantic Ocean, which stretches from the North Pole to the South Pole. Mid-ocean ridges are areas of much volcanic and earthquake activity. Converging plates: In many places the huge plates of the earth's surface are slowly moving together with unimaginable force. Sometimes the edge of one plate is gradually destroyed by the force of collision, sometimes the impact simply crimps the plates' edges, thereby creating great mountain ranges. When one tectonic plate bends beneath the other, it is called subduction. Most of the time this happens because a dense oceanic plate collides with a lighter continental plate. You can see this along the Pacific coast of South- America. The oceanic plate dips beneath into the Asthenosphere. Through the heat of the Asthenosphere the subducted plate melts. At the surface an ocean trench is created, followed by an arc of islands. In this area also volcanic activities and earthquakes occur. Seafloor Spreading Studies show that volcanic activity under the sea causes magma from beneath the earth’s crust to rise to the surface, forming a very long ridge along the middle of the oceans that separate the large continents. When continental plates collide, one of the plates splits up into two layers: a lower layer of dense mantle rock and an upper layer of lighter crystal rock. As the mantle layer subducts, the upper layer is peeled off and crumples up against the other plate, thus forming mountain ranges, like the Alps. These are called crumpled mountains. Science I - 15 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. DIASTROPHISM – the process which involves movements of the earth’s crust such that a portion id pushed up, push down or forced sideways Folding – the process when the sideward forces acting on rocks deform the rocks into wavelike folds after tilting, bending of wrinkling. Faulting sliding or moving over of rock layers over one another along the break or fracture, may occur vertically or horizontally. Volcanoes A Volcano is a gap in the earth where molten rock and other materials come to the earth's surface. Some volcanoes are just cracks in the earth's crusts. Others are weak places in the earth's crust, which occur on places where magma bubbles up through the crust and comes to the earth's surface. Magma is molten rock that occurs by partial melting of the crust and the mantle by high temperatures deep down in the ground. Once magma comes to the earth's surface it is called lava. ACTIVE AND NON-ACTIVE VOLCANOES Science I - 16 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. There are volcanoes in different phases of activity: Active volcanoes, which are likely to erupt at any moment, dormant volcanoes, which lie dormant for centuries, but then erupt suddenly and violently, and extinct volcanoes, ones no longer likely to erupt. TYPES OF VOLCANOES The ordinary volcanoes can be divided in different types, relating to their forms: The shield volcano: This is a broad, shallow volcanic cone, which arises because the running lava, which is fluid and hot, cools slowly. The dome volcano: This one has a steep, convex slope from thick, fast- cooling lava The ash-cinder volcano: Throws out - besides lava - much ash into the air. Through this the volcanic cone is built up from alternate layers of ash and cinder. The composite volcano: These are also built up from alternate layers of lava and ash but, besides its main crater, it has many little craters on its slope. The caldera volcano: An older volcano with a large crater which can be 62 miles(100km) wide. In this crater many little new craters are formed. Earthquakes An Earthquake is in fact the shaking of the ground caused by sudden movements in the earth's crust. The biggest earthquakes are set off by the movement of tectonic plates. Some plates slide past each other gently, but others can cause a heavy pressure on the rocks, so they finally crack and slide past each other. By this, vibrations or shock waves are caused, which go through the ground. It is these vibrations or seismic waves which cause an earthquake. The closer to the source of the earthquake (the focus or hypocenter), the more damage occurs. Earthquakes are classified according to the depth of the focus. 0-43 miles (0-70 km) below ground: shallow earthquakes 43-186 miles (70-300 km) below ground: intermediate earthquakes deeper than 186 miles (300 km) below ground: deep earthquakes Science I - 17 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. The closer the focus to the surface, the heavier the earthquake. The earthquake is always the most intense on the surface directly above the focus (Epicenter). In general big earthquakes begin with light vibrations (foreshocks). These are the initial fractures in the rocks. After the main shock, there may be minor aftershocks, most of the time for months. This occurs as the rocks settle down. Rocks Rocks are classified in three types based on how they are formed. a. Igneous rocks are formed when molten rock (magma) from within Earth cools and solidifies. There are two types: intrusive igneous rocks solidify beneath Earth's surface; extrusive igneous rocks solidify at the surface. Examples: Granite, basalt, obsidian b. Sedimentary rocks are formed when sediment (bits of rock plus material such as shells and sand) gets packed together. They can take millions of years to form. Most rocks that you see on the ground are sedimentary. Examples: Limestone, sandstone, shale c. Metamorphic rocks are sedimentary or igneous rocks that have been transformed by heat, pressure or both. Metamorphic rocks are usually formed deep within Earth, during a process such as mountain building. Examples: Schist, marble, slate THE ROCK CYCLE The three major types of rocks, igneous, sedimentary, and metamorphic rocks are interrelated by a series of natural processes. Igneous rocks form from the cooling and crystallization of hot molten lava and magma. Igneous rocks undergo weathering and erosion to form sediments. Sediments are deposited and lithified by compaction and cementation to form sedimentary rocks. Sedimentary rock become buried by additional sedimentary deposition, and when they are deep within the Earth, they are subjected to heat and pressure which causes them to become metamorphic rocks. With further burial and heating, the metamorphic rocks begin to melt. Partially molten metamorphic rocks are known as migmatite. As melting proceeds with increasing temperatures and depths of burial, eventually the rock becomes molten and becomes magma, which cools and crystallizes to form plutonic igneous rock, or which is erupted onto the Earth's surface as lava, and cools and crystallizes to form volcanic igneous rock. Further complications within the rock cycle include (1) weathering of sedimentary and metamorphic rocks (in addition to igneous rocks), and (2) metamorphism of igneous rocks and repeated metamorphism of metamorphic rocks. WEATHERING – Breaking down of rocks brought about by either physial or chemical means giving rise to sediments or ther rock fragments Science I - 18 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Types of Weathering A. Physical or mechanical weathering Frost wedging - water expands when it freezes Exfoliation or unloading - o rock breaks off into leaves or sheets along joints which parallel the ground surface; o caused by expansion of rock due to uplift and erosion; removal of pressure of deep burial; Thermal expansion - o repeated daily heating and cooling of rock; o heat causes expansion; cooling causes contraction. o different minerals expand and contract at different rates causing stresses along mineral boundaries. B. Chemical weathering Rock reacts with water, gases and solutions (may be acidic); will add or remove elements from minerals. Dissolution (or solution) - o Several common minerals dissolve in water halite calcite o Limestone and marble contain calcite and are soluble in acidic water o Marble tombstones and carvings are particularly susceptible to chemical weathering by dissolution. Note that the urn and tops of ledges are heavily weathered, but the inscriptions are somewhat sheltered and remain legible. o Caves and caverns typically form in limestone speleothems are cave formations speleothems are made of calcite form a rock called travertine stalactites - hang from ceiling stalagmites - on the ground o Karst topography forms on limestone terrain and is characterized by: caves/caverns, sinkholes, disappearing streams, springs Science I - 19 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Oxidation o Oxygen combines with iron-bearing silicate minerals causing "rusting" o Iron oxides are produced. Iron oxides are red, orange, or brown in color o Mafic rocks such as basalt (which may contain olivine, pyroxene, or amphibole) weather by oxidation to an orange color o "Georgia Red Clay" derives its color from the oxidation of iron bearing minerals Hydrolysis C. Biological weathering Organisms can assist in breaking down rock into sediment or soil. 1. Roots of trees and other plants 2. Lichens, fungi, and other micro-organisms 3. Animals (including humans) EROSION- the process by which rock fragments and sediments are carried along by such agents as wind and running water DEPOSITION- the process by which rock fragments and sediments ae carried by agents of erosion are dropprd or deposited in other places. COMPACTING – the process by which rock fragments and other materials that accumulated, usually at the bottom of a thick column of water, get cemented together and harden into rock METAMORPHISM - a change in constitution of a rock brought about by pressure, heat and chemical action resulting in a more compact and highly crystalline condition of the rock. MELTING COOLING AND SOLIDIFYING Minerals and Gems Minerals are solid, inorganic (not living) substances that are found in and on earth. Most are chemical compounds, which means they are made up of two or more elements. For example, the mineral sapphire is made up of aluminum and oxygen. A few minerals, such as gold, silver and copper, are made from a single element. Minerals are considered the building blocks of rocks. Rocks can be a combination of as many as six minerals. Science I - 20 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Many minerals, such as gold and silver, are very valuable because they are beautiful and rare. Limestone, clay and quartz are other examples of minerals. Gems are minerals or pearls that have been cut and polished. They are used as ornaments, such as jewelry. Precious stones are the most valuable gems. They include diamonds, rubies and emeralds Atmosphere What is Atmosphere? The earth is surrounded by all kind of gases. This layer is called the earth's Atmosphere. Without this atmosphere life on earth isn't possible. It gives us air, water, heat, and protects us against harmful rays of the sun and against meteorites. Science I - 21 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. This layer around the earth is a colorless, odorless, tasteless 'sea' of gases, water and fine dust. The atmosphere is made up of different layers with different qualities. It consists of 78 percent nitrogen, 21 percent oxygen, 0.93 percent argon, 0.03 percent carbon dioxide and 0.04 percent of other gases. The Troposphere is the layer where the weather happens. Above this layer is the Stratosphere and in between them is the Ozone layer, that absorbs the sun's harmful ultraviolet rays. Above the Stratosphere is the Mesosphere, the Thermosphere including the Ionosphere - and the Exosphere. The atmosphere measures about 500 miles (800km). Layers of the Atmosphere THE TROPOSPHERE The Troposphere is the lowest layer of the atmosphere and measures about 7 miles(12 km). It contains over 75 percent of all the atmosphere's gases and vast quantities of water and dust. As the sun heats the ground, it keeps this thick mixture churning. The weather is caused by these churnings of the mass. The troposphere is normally warmest at ground level and cools higher up where it reaches its upper boundary (the tropopause). The tropopause varies in height. At the equator it is at 11.2 miles(8 km) high, at 50 N and 50 S, 5.6 miles(9 km) and at the poles 3.7 miles(6 km) high. STRATOSPHERE The Stratosphere extends from the tropopause up to its boundary (the Stratopause), 31 miles(50 km) above the Earth's surface. In this layer there is 19 percent of the atmosphere's gases and it contains little water vapour. Compared to the troposphere it is calm in this layer. The movements of the gases are slow. Within the stratosphere is the ozone layer, a band of ozone gas, that absorbs harmful ultraviolet rays of the sun. The higher you get in the atmosphere, the warmer the air gets. The temperature rises from -76 ºF(-60 ºC) at the bottom to a maximum of about 5 ºF(10 ºC) at the stratopause. MESOSPHERE The mesosphere is the next layer above the stratopause and extends to its upper boundary (the Mesopause), at 50 miles(80 km) above the ground. The gases in the mesosphere are too thin to absorb much of the sun's heat. Although the air is still thick enough to slow down meteorites hurtling into the atmosphere. They burn up, leaving fiery trails in the night sky. The temperatures in the mesosphere drop to -184 ºF(-120 ºC) at the mesopause. THERMOSPHERE The Thermosphere is the layer above the mesopause. The gases of the thermosphere are even thinner than those in the mesosphere, but they absorb ultraviolet light from the sun. Because of this, the temperatures rise to 3,600 ºF (2,000 ºC) at the top. This is at a height of 430 miles (700 km) of the earth's surface. In the thermosphere is a separate layer, the Ionosphere. This layer extends of 62 miles(100 km) to 190 miles(300 km) of the earth's surface. Science I - 22 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. IONOSPHERE The ionosphere is part of the thermosphere. It is made of electrically charged gas particles (ionised). The particles get this electric charge by ultraviolet rays of the sun. The ionosphere has the important quality of bouncing radio signals, transmitted from the earth. That’s why places all over the world can be reached via radio. EXOSPHERE The Exosphere is the outermost layer of the atmosphere and extends from 430 miles (700 km) to 500 miles (800 km) above the ground. In this layer gases get thinner and thinner and drift off into space. What influence does the Atmosphere have? The atmosphere is of vital importance for life on earth. Without atmosphere life would be impossible. It gives us air to breathe and protects us from meteorites and ultraviolet rays from the sun. The atmosphere absorbs so much heat that temperatures on earth are such that life is possible. The weather, that exists by constant circulation of water to water vapor, to rain to water. This cycle causes, together with the differences in temperature and circulation of air (wind), erosion of the earth's surface. By erosion the outside of the earth changes through the years. Air AIR MOVEMENT Warm air is less dense than cold air. Thus, warm air rises above cold air making the pressure below lower. The horizontal movement of air from high pressure area to lower pressure area produces wind. SEA BREEZES AND LAND BREEZES When spending a day at the beach, a noticeable drop in temperature may occur during the early afternoon as a cool breeze begins to blow off of the water. This wind is known as the "sea breeze", which occurs in response to differences in temperature between a body of water and neighboring land. Science I - 23 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Sea-breeze circulations most often occur on warm sunny days during the spring and summer when the temperature of the land is normally higher than the temperature of the water. During the early morning hours, the land and the water start out at roughly the same temperature. On a calm morning, a given pressure surface will be at the same height above both the land and water. A few hours later, the sun's energy begins to warm the land more rapidly than the water. By later in the day, the temperatures of the land increases while the temperature of the water remains relatively constant. This occurs because water, especially large bodies of water like a lake or ocean, are able to absorb more energy than land without warming. It is important to remember that the air is not heated directly from above by the sun. In fact, most of the incoming solar energy actually passes right through the atmosphere. However, as the land absorbs this energy, heat is radiated back into the atmosphere (from the earth), warming the overlying air. Some of this heat is transported to higher levels in the atmosphere through convection. On the other hand, since the temperature of the water remains relatively constant throughout the day, the air over the water is not heated from below (as over land), resulting in lower air temperatures over the water. On clear, calm evenings, temperature differences between a body of water and neighboring land produce a cool wind that blows offshore. This wind is called a "land breeze". Land breezes are strongest along the immediate coastline but weaken considerably further inland. Land-breeze circulations can occur at any time of year, but are most common during the fall and winter seasons when water temperatures are still fairly warm and nights are cool. Science I - 24 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. On clear and calm evenings, the earth's surface cools by radiating (giving off) heat back into space, and this results in a cooling of the immediately overlying air. Since the air over land cools more rapidly than the air over water, a temperature difference is established, with cooler air present over land and relatively warmer air located over water. AIR POLLUTION When large amount of dust, soot, bacteria, and other harmful gases get into the air, air is being polluted. Today, the main sources of air pollution in the Philippines are : 1) industry and 2) transportation. Major Air Pollutants Pollutant Sources Effects Ozone is not created directly, but is formed when nitrogen Ozone near the ground can oxides and volatile organic cause a number of health compounds mix in sunlight. problems. Ozone can lead Ozone. A gas that can be found That is why ozone is mostly to more frequent asthma in two places. Near the ground found in the summer. attacks in people who have (the troposphere), it is a major Nitrogen oxides come from asthma and can cause sore part of smog. Higher in the air burning gasoline, coal, or throats, coughs, and (the stratosphere), it helps block other fossil fuels. There are breathing difficulty. It may radiation from the sun. many types of volatile even lead to premature organic compounds, and they death. Ozone can also hurt come from sources ranging plants and crops. from factories to trees. Carbon monoxide is released Carbon monoxide makes it when engines burn fossil hard for body parts to get fuels. Emissions are higher the oxygen they need to when engines are not tuned run correctly. Exposure to Carbon monoxide. A gas that properly, and when fuel is not carbon monoxide makes comes from the burning of completely burned. Cars emit people feel dizzy and tired fossil fuels, mostly in cars. It a lot of the carbon monoxide and gives them headaches. cannot be seen or smelled. found outdoors. Furnaces and Elderly people with heart heaters in the home can emit disease are hospitalized high concentrations of carbon more often when they are monoxide, too, if they are not exposed to higher amounts Science I - 25 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. properly maintained. of carbon monoxide. High levels of nitrogen dioxide exposure can give Nitrogen dioxide mostly people coughs and can comes from power plants and make them feel short of cars. Nitrogen dioxide is breath. People who are formed in two ways—when Nitrogen dioxide. A reddish- exposed to nitrogen nitrogen in the fuel is burned, brown gas that comes from the dioxide for a long time or when nitrogen in the air burning of fossil fuels. It has a have a higher chance of reacts with oxygen at very strong smell at high levels. getting respiratory high temperatures. Nitrogen infections. Nitrogen dioxide can also react in the dioxide reacts in the atmosphere to form ozone, atmosphere to form acid acid rain, and particles. rain, which can harm plants and animals. Particulate matter can be divided into two types— Particulate matter that is Particulate matter. Solid or coarse particles and fine small enough can enter the liquid matter that is suspended particles. Coarse particles are lungs and cause health in the air. To remain in the air, formed from sources like problems. Some of these particles usually must be less road dust, sea spray, and problems include more than 0.1-mm wide and can be as construction. Fine particles frequent asthma attacks, small as 0.00005 mm. are formed when fuel is respiratory problems, and burned in automobiles and premature death. power plants. Sulfur dioxide exposure can affect people who have Sulfur dioxide mostly comes asthma or emphysema by from the burning of coal or making it more difficult for Sulfur dioxide. A corrosive gas oil in power plants. It also them to breathe. It can also that cannot be seen or smelled comes from factories that irritate people's eyes, at low levels but can have a make chemicals, paper, or noses, and throats. Sulfur “rotten egg” smell at high fuel. Like nitrogen dioxide, dioxide can harm trees and levels. sulfur dioxide reacts in the crops, damage buildings, atmosphere to form acid rain and make it harder for and particles. people to see long distances. Lead. A blue-gray metal that is Outside, lead comes from High amounts of lead can Science I - 26 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. very toxic and is found in a cars in areas where unleaded be dangerous for small number of forms and locations. gasoline is not used. Lead can children and can lead to also come from power plants lower IQs and kidney and other industrial sources. problems. For adults, Inside, lead paint is an exposure to lead can important source of lead, increase the chance of especially in houses where having heart attacks or paint is peeling. Lead in old strokes. pipes can also be a source of lead in drinking water. Each toxic air pollutant comes from a slightly different source, but many are Toxic air pollutants can Toxic air pollutants. A large created in chemical plants or cause cancer. Some toxic number of chemicals that are are emitted when fossil fuels air pollutants can also known or suspected to cause are burned. Some toxic air cause birth defects. Other cancer. Some important pollutants, like asbestos and effects depend on the pollutants in this category formaldehyde, can be found pollutant, but can include include arsenic, asbestos, in building materials and can skin and eye irritation and benzene, and dioxin. lead to indoor air problems. breathing problems. Many toxic air pollutants can also enter the food and water supply. If the ozone in the CFCs are used in air Stratospheric ozone depleters. stratosphere is destroyed, conditioners and Chemicals that can destroy the people are exposed to more refrigerators, since they work ozone in the stratosphere. These radiation from the sun well as coolants. They can chemicals include (ultraviolet radiation). This also be found in aerosol cans chlorofluorocarbons (CFCs), can lead to skin cancer and and fire extinguishers. Other halons, and other compounds eye problems. Higher stratospheric ozone depleters that include chlorine or ultraviolet radiation can are used as solvents in bromine. also harm plants and industry. animals. Science I - 27 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. The greenhouse effect can Carbon dioxide is the most lead to changes in the Greenhouse gases. Gases that important greenhouse gas. It climate of the planet. Some stay in the air for a long time comes from the burning of of these changes might and warm up the planet by fossil fuels in cars, power include more temperature trapping sunlight. This is called plants, houses, and industry. extremes, higher sea levels, the “greenhouse effect” because Methane is released during changes in forest the gases act like the glass in a the processing of fossil fuels, composition, and damage greenhouse. Some of the and also comes from natural to land near the coast. important greenhouse gases are sources like cows and rice Human health might be carbon dioxide, methane, and paddies. Nitrous oxide comes affected by diseases that nitrous oxide. from industrial sources and are related to temperature decaying plants. or by damage to land and water. Weather and Climate WEATHER- describes the condition of the atmosphere in a particular time (cool and dry, humid, windy, rainy, or stormy) CLIMATE- average weather in a region over a number of years or usually decades (tropical) CLOUDS - little drops of water or ice hanging in the atmosphere. A ceilometer measures the height of clouds. Cloud Type Descriptive Name Description Cirrus Mare's tails thin, feathery Cirrocumulus Mackerel sky small patches of white Cirrostratus Bed sheet clouds thin, white sheets Science I - 28 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Stratus High fogs low, gray blanket Cumulus Cauliflowers flat-bottomed, white puffy Cumulonimbus Thunderheads mountains of heavy, dark clouds Winds WIND SYSTEMS The major wind systems in the Philippines are a. Northeast Trade Winds – from north, north east and east b. Southwest Monsoon (habagat) – originates from Southeast Trade winds south of the equator c. Northeast monsoon (amihan)- from east, south east CYCLONES – low pressure areas in the tropics a. tropical depresssion- with wind speed of less than 63 kph b. trpical storm – with wind speed of 63-118 kph c. typhoon – with wind speed of more than 118 lph Thunderstorms Thunderstorms affect small areas when compared with hurricanes and winter storms. The typical thunderstorm is 15 miles in diameter and lasts an average of 30 minutes. Nearly 1,800 thunderstorms are happening at any moment around the world. That's 16 million a year! Despite their small size, all thunderstorms are dangerous. Every thunderstorm produces lightning, which kills more people each year than tornadoes. Strong winds, hail, and tornadoes are also dangers associated with some thunderstorms. You can estimate how many miles away a storm is by counting the number of seconds between the flash of lightning and the clap of thunder. Divide the number of seconds by five to get the distance in miles. The lightning is seen before the thunder is heard because light travels faster than sound. Thunderstorms need three things: Science I - 29 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. Moisture—to form clouds and rain. Unstable Air—relatively warm air that can rise rapidly. Lift—fronts, sea breezes and mountains are capable of lifting air to help form thunderstorms. Lightning The action of rising and descending air within a thunderstorm separates positive and negative charges. Water and ice particles also affect the distribution of electrical charge. Lightning results from the buildup and discharge of electrical energy between positively and negatively charged areas. Most lightning occurs within the cloud or between the cloud and ground. The average flash of lightning could turn on a 100-watt light bulb for more than 3 months. The air near a lightning strike is hotter than the surface of the sun! The rapid heating and cooling of air near the lightning channel causes a shock wave that results in thunder. Your chances of being struck by lightning are estimated to be 1 in 600,000 but those chances can be reduced by following safety rules. Most lightning deaths and injuries occur when people are caught outdoors, and most happen in the summer. Many fires in the western United States and Alaska are started by lightning. In the past 10 years, more than 15,000 fires have been started by lightning. The Ozone Layer Ozone is a molecule containing three oxygen atoms. It is blue in color and has a strong odor. Normal oxygen, which we breathe, has two oxygen atoms and is colorless and odorless. Ozone is much less common than normal oxygen. Out of each 10 million air molecules, about 2 million are normal oxygen, but only 3 are ozone. However, even the small amount of ozone plays a key role in the atmosphere. The ozone layer absorbs a portion of the radiation from the sun, preventing it from reaching the planet's surface. Most importantly, it absorbs the portion of ultraviolet light called UVB. UVB has been linked to many harmful effects, including various types of skin cancer, cataracts, and harm to some crops, certain materials, and some forms of marine life. At any given time, ozone molecules are constantly formed and destroyed in the stratosphere. The total amount, however, remains relatively stable. While ozone concentrations vary naturally with sunspots, the seasons, and latitude, these processes are well understood and predictable. Each natural reduction in ozone levels has been followed by a recovery. Recently, however, convincing scientific evidence has shown that the ozone shield is being depleted well beyond changes due to natural processes. Science I - 30 - Feel free to pass this on to your friends, but please don’t post it online. Discuss UPCAT and other college entrance exam questions and answers at Academic-Clinic’s Facebook Page. We encourage you to answer the questions we post there and actively participate in the discussions on our wall. For UPCAT, ACET, DLSUCET and USTET tips, tricks, news and other college entrance exam information, visit the Academic-Clinic website. Tell your friends and classmates to come find and join us. The more, the merrier. Good luck! Academic- Academic-Clinic.com The achiever’s guide to academic life and beyond… Website: http://academic-clinic.com Facebook: http://www.facebook.com/academic.clinic Twitter: http://twitter.com/acadclinic College entrance exam and science high school entrance test tips. Conquer UPCAT, ACET, USTET, DLSUCET, PSHS-NCE, and other entrance tests. CFCs - are stable substances that only exposure to strong UV radiation breaks them down. When that happens, the CFC molecule releases atomic chlorine. One chlorine atom can destroy over 100,000 ozone molecules. The net effect is to destroy ozone faster than it is naturally created. Astronomy The Universe How old is the universe? What is it made of? For the first time, scientists have clarity. 13.7 billion years: Age of the universe 200 million years: Interval between the Big Bang and the appearance of the first stars 4%: Proportion of the universe that is ordinary matter 23%: Proportion that is dark matter 73%: Proportion that is dark energy COLORS OF THE UNIVERSE Blue Planets - Earth, Neptune, and Uranus are all blue because of gases in their atmosphere. Blue Stars - These are the hottest stars, with a surface temperature of more than 37,000°F. Yellow Stars - These are warm stars, such as the Sun. Their temperature is about 10,000°F. Red Stars- The coolest stars are red. Their surface temperature is less than 5,500°F. Red Shift - When light coming from a distant star is seen through a spectroscope (an instrument that separates light into its different colors); the light we receive continues to

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