Science Study PDF

Science Study Key Areas to Study Into the Atom Describe the particle arrangement of solids, liquids and gasses Describe the kinetic energy of particles in solids, liquids and gasses and the effect of adding heat. Define waves as carriers of energy Label the...

Science Study Key Areas to Study Into the Atom Describe the particle arrangement of solids, liquids and gasses Describe the kinetic energy of particles in solids, liquids and gasses and the effect of adding heat. Define waves as carriers of energy Label the order of types of radiation in the electromagnetic spectrum Describe the different properties of radiation from the electromagnetic spectrum including their uses in everyday life such as: communication and medical applications Explain the relationship between the frequency and wavelength of an EM wave and the amount of energy it transfers Define the transmission of sound as the vibration of particles through a medium Explain how the movement of sound through solids, liquids and gasses are different, referring to particles Electricity Identify circuit symbols Draw circuit symbols and diagrams Describe a simple circuit Understand how a simple circuit works Construct series and parallel circuits Compare the structure and function of series and parallel circuits Describe advantages and disadvantages of series and parallel circuits Outline applications of series and parallel circuits Describe the relationship between voltage, current and resistance Use ammeters and voltmeters correctly to measure current and voltage Building a Sustainable Future Define key terms related to ecosystems Distinguish between biotic and abiotic features of ecosystems Identify that ecosystems consist of communities of interdependent organisms and abiotic components of environments Analyse and construct food chains and food webs to show the flow of energy in ecosystems.  Science Study Classify organisms using the appropriate terminology e.g. autotroph (producer), Heterotroph (consumer), herbivores, omnivores, carnivores, decomposers. Analyse how changes in some biotic and abiotic components of an ecosystem affect populations and/or communities Predict the impact of population changes in an ecosystem using food webs Describe Ecological relationships and Symbiosis Working Scientifically planning and selecting appropriate investigation methods to collect reliable data specifying the dependent and independent variables for controlled experiments assessing risks and addressing ethical issues associated with these methods selecting and extracting information from tables and column or line graphs analysing patterns and trends, including identifying inconsistencies in data and information assessing the validity and reliability of first-hand data critically analysing the validity of information from secondary sources using cause-and-effect relationships to explain ideas Electricity Vocabulary list Neutral having no strongly marked or positive characteristics or features. a stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal Protons in magnitude to that of an electron. a stable subatomic particle with a charge of negative electricity, found in all atoms and acting Electrons as the primary carrier of electricity in solids. Neutrons subatomic particles found inside the nucleus of every atom.  Science Study Repel drive or force (an attack or attacker) back or away. Electricity the movement of electrons between atoms Batteries consist of two electrical terminals called the cathode and the anode, separated by a Battery chemical material called an electrolyte Load the force exerted on a surface or body. an electrical component that can disconnect or connect the conducting path in an electrical Switch circuit, interrupting the electric current or diverting it from one conductor to another. an electrical component that limits or regulates the flow of electrical current in an electronic Resistor circuit Circuit a complete circular path that electricity flows through Current the rate at which electrons flow past a point in a complete electrical circuit Coulomb tandard unit of electric charge in the International System of Units (SI) Voltage the pressure from an electrical circuit's power source that pushes charged electrons Voltmeter instrument that measures voltages of either direct or alternating electric current on a scale Amperes the unit of electric current in the International System of Units Ammeter an instrument used to measure the current in a circuit Conductor a substance or material that allows electricity to flow through it Insulator A substance or material that doesnt allow electricity to flow through it Resistance the opposition that a substance offers to the flow of electric curren  Science Study a measurement of resistance between two points of a conductor when a constant potential Ohms difference of one volt (V) is applied to those points and a current of one ampere (A) is produced. an electrical safety device that operates to provide overcurrent protection of an electrical Fuse circuit Series circuit the circuit elements are arranged in a single path Parallel circuit A parallel circuit has two or more paths for current to flow through Analogy a comparison of the similarities between two concepts. a device that transforms mechanical energy into electrical energy, typically by electromagnetic Electric generator induction via Faraday's Law Greenhouse gas gases in the earth's atmosphere that trap heat Definition of Electricity Electricity: The flow of electrons through a material Key Terms Conductor: A material that allows electrons to flow freely (e.g., metals like copper and aluminum). Insulator: A material that does not allow electrons to flow easily (e.g., rubber, glass, and plastic). Resistor: A component that limits the flow of electric current in a circuit. Classification of Materials Conductors: Copper, aluminum, silver, gold. Insulators: Rubber, wood, glass, plastic. Resistors: Carbon, metal film, wire-wound resistors. Common Uses Conductors: Wiring in homes and electronics. Insulators: Coating on wires, electrical appliances. Resistors: Current control in electronic circuits.  Science Study Circuit Circuit diagrams are like maps that show how different parts of an electrical circuit are connected. These diagrams use symbols to represent each part of the circuit. Each symbol represents a different component, like a battery, a light bulb, or a switch. For example, a battery is represented by a long line and a short line, with the long line representing the positive terminal and the short line representing the negative terminal. A light bulb is represented by a circle with a loop inside. These symbols are important because they allow us to understand how electricity flows through a circuit. Electricity flows in a closed loop, starting at the positive terminal of the battery, going through the wires and components, and then returning to the negative terminal of the battery. If the circuit is broken, the electricity cannot flow, and the components won't work. For example, if you have a circuit with a battery, a switch, and a light bulb, the electricity will flow from the battery, through the switch, through the light bulb, and back to the battery. If the switch is open, the circuit is broken, and the light bulb won't light up. Circuit diagrams are used by engineers and scientists to design and build electrical circuits. They are also used to troubleshoot problems with circuits, by helping to identify where the problem might be. Learning how to read and draw circuit diagrams is a valuable skill that can be used in many different fields. When drawing circuit diagrams, there are a few rules to follow. Wires are drawn as straight lines, and they should not cross over each other. The correct symbols must be used for each component, and the circuit must form a closed loop. By following these rules, you can create clear and accurate circuit diagrams that can be easily understood by others. Circuit Symbols SYMBOL NAME SYMBOL NAME CELL AMMETER BATTERY VOLTMETER CLOSED RESISTOR SWITCH  Science Study OPEN SWITCH VARIABLE RESISTOR WIRE LIGHT/GLOBE/ LOAD Series and Parallel Circuits Series Circuit: Components connected in a single path; current is the same throughout, voltage divides. Parallel Circuit: Components connected across multiple paths; voltage is the same across all, current divides. Comparison of Circuits Advantages of Series Circuits: Simple, fewer components. Disadvantages of Series Circuits: If one component fails, the entire circuit fails. Advantages of Parallel Circuits: If one component fails, others remain functional. Disadvantages of Parallel Circuits: More complex, requires more materials. Applications of Circuits Series: Christmas lights. Parallel: Home wiring systems. Key Electrical Concepts Voltage: The electrical potential difference, measured in volts (V). Current: The flow of electric charge, measured in amperes (A). Resistance: Opposition to current flow, measured in ohms (Ω). Relationships Ohm's Law: V = I × R (Voltage = Current × Resistance). Measurement Tools Ammeter: Measures current; connected in series. Voltmeter: Measures voltage; connected in parallel. Factors Affecting Resistance Material type, length of conductor, cross-sectional area, temperature. Safety with Electricity Identify dangers: Shock, short circuits, fire.  Science Study Safe practices: Use insulated tools, avoid wet conditions, check for damaged wires. Safety devices: Circuit breakers, fuses, RCDs. Historical Contributions Alessandro Volta: Developed the first chemical battery (Voltaic pile). Oersted: Discovered the relationship between electricity and magnetism. Faraday: Developed concepts of electromagnetic induction. Electricity Generation Using Magnets: Generate electricity through electromagnetic induction. NSW Power Generation: Identify sources (coal, hydro, wind). Coal-Fired Power Stations: Burn coal to produce steam that drives turbines. Sustainable Methods Example: Wind energy – turbines convert wind energy into electricity. Into the atom Definitions Atom the smallest particle of a chemical element that can exist. Electron a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids. Proton a stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron. Neutron a subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen. Nucleus the positively charged central core of an atom, consisting of protons and neutrons and containing nearly all its mass. Orbit the curved path of a celestial object or spacecraft round a star, planet, or moon, especially a periodic elliptical revolution. Element an essential or characteristic part of something abstract. Compound an essential or characteristic part of something abstract. Metal A substance with high electrical conductivity, luster, and malleability, which readily loses electrons to form positive ions (cations). Non-metal an element or substance that is not a metal  Science Study Halogen one of a group of chemical elements that includes chlorine, fluorine, and iodine Inert lacking the ability or strength to move. Metalloid an element that has properties that are intermediate between those of metals and (semi-metal nonmetals ) Acid a molecule or other species which can donate a proton or accept an electron pair in reactions. Base the lowest part or edge of something, especially the part on which it rests or is supported. Alkali a compound with particular chemical properties including turning litmus blue and neutralizing or effervescing with acids; typically, a caustic or corrosive substance of this kind such as lime or soda. Conduction and convection Process Description Conduction Conduction is how heat transfers through direct contact with SOLID objects that are touching. Any time that two objects or substances touch, the hotter object passes heat to the cooler object. Imagine that you place one end of a metal pole into a fire. The molecules on the fire end will get hot. Each hot molecule will pass the heat along to the molecule next to it, which will pass the heat along to the next molecule, and so on. Before you know it, the heat has traveled all the way along the metal pole until it reaches your hand Convection Convection is how heat passes through fluids (liquids and gases). A fluid is anything that has loosely moving molecules that can move easily from one place to another. One important property of fluids particles is that they rise when heated. That’s because the molecules spread out and move apart when they get hot. The hot fluid becomes less dense and rises up. Cooler fluid is more dense and so it sinks down. This up-and-down motion creates what are called convection currents. Convection currents are circular movements of heated fluids that help spread the heat. HEAT/ENERGY TRANSFER - RADIATION A final method of heat transfer involves radiation. Radiation is the transfer of heat by means of electromagnetic waves. To radiate means to send out or spread from a central location. Whether it is light, sound, waves, rays, flower petals, wheel spokes or pain, if something radiates then it protrudes or spreads outward from an origin. The transfer of heat by radiation involves the carrying of energy from an origin to the space surrounding it. The energy is carried by electromagnetic waves and does not involve the movement or the interaction of matter. Thermal radiation can occur through matter or through a region of space that is void of matter (i.e., a vacuum). In fact, the heat received on Earth from the sun is  Science Study the result of electromagnetic waves traveling through the void of space between the Earth and the sun. The hotter the object, the more it radiates. The sun obviously radiates off more energy than a hot mug of coffee. The temperature also affects the wavelength and frequency of the radiated waves. Objects at typical room temperatures radiate energy as infrared waves. Being invisible to the human eye, we do not see this form of radiation. An infrared camera is capable of detecting such radiation. Perhaps you have seen thermal photographs or videos of the radiation surrounding a person or animal or a hot mug of coffee or the Earth. Thermal radiation is a form of heat transfer because the electromagnetic radiation emitted from the source carries energy away from the source to surrounding (or distant) objects. This energy is absorbed by those objects, causing the average kinetic energy of their particles to increase and causing the temperatures to rise. In this sense, energy is transferred from one location to another by means of electromagnetic radiation. The image at the right was taken by a thermal imaging camera. The camera detects the radiation emitted by objects and represents it by means of a color photograph. Waves Waves are a fascinating part of the world around us, and they come in two main types: transverse and longitudinal. These waves are different in the way they move and how they transfer energy.  Science Study Transverse waves are like ripples on a pond. The particles in a transverse wave move up and down, perpendicular to the direction the wave travels. Imagine shaking a rope up and down; the wave travels along the rope, but the rope itself doesn't move forward. Other examples of transverse waves include light waves, which allow us to see, and seismic S-waves, which are a type of earthquake wave. Longitudinal waves, on the other hand, move in the same direction as the particles vibrate. Think of a slinky spring. If you push and pull one end, the compressions and expansions travel along the spring. Sound waves are a good example of longitudinal waves. When you speak, your vocal cords create vibrations in the air, which travel as compressions and rarefactions, reaching your ears. Both transverse and longitudinal waves transfer energy without transferring matter. This means that the particles in the medium carrying the wave don't move along with the wave; they just oscillate back and forth. The energy is what travels from one point to another. To remember the difference between the two types of waves, think of the letters "T" and "L." Transverse waves have vibrations perpendicular to the direction of travel, like the letter "T" standing upright. Longitudinal waves have vibrations parallel to the direction of travel, like the letter "L" lying down. Electromagnetic waves are a type of wave that is caused by oscillations in an electromagnetic field. These oscillations are changes in electrical and magnetic fields that occur at right angles to the direction the wave is travelling. All electromagnetic waves transfer energy from a source to an absorber. They can travel through a vacuum, like space, and they all travel at the same speed through a vacuum or air. The speed of electromagnetic waves in a vacuum is 300,000,000 metres per second (m/s). Electromagnetic waves are grouped together in a continuous series called the electromagnetic spectrum. This spectrum includes waves with a very short wavelength, high frequency, and high energy, as well as waves with a very long wavelength, low frequency, and low energy. The electromagnetic spectrum is divided into seven distinct groups: radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays. These groups are arranged in order of decreasing wavelength and increasing frequency. The different types of radiation in the electromagnetic spectrum have different uses and dangers depending on their wavelength and frequency. For example, radio waves are used for communication, such as television and radio, mobile phones, radar, Wi-Fi, and Bluetooth. Microwaves are used for cooking, satellite communication, and speed cameras. Infrared radiation is used for heat transfer by radiation, such as electric heaters and cooking by grilling, as well as night vision equipment, optical fibre communication, TV remote control, and burglar alarms. Visible light is the only part of the electromagnetic spectrum that can be detected by the human eye. It appears as various wavelengths on the spectrum, each of which corresponds to a different colour. When all these frequencies are combined, they appear as white light. Ultraviolet radiation is used for suntans, detecting forged bank notes, helping to make vitamin D, hardening some types of dental filling, and in nightclubs and bowling alleys to make clothes glow. X-rays are used for medical images of bones and airport baggage scanners. Gamma radiation is used for killing cancer cells, sterilising medical equipment, and killing bacteria to prolong the shelf life of fruit. Science Study  Science Study explain why sound travels through solids faster than liquids and gases. Sound waves transmit energy by vibrating particles and need to travel through a medium. The sound waves move through mediums by vibrating the molecules in the direction of energy transfer. The molecules in solids are packed very tightly, as a result, the particles hit and vibrate each other more easily and therefore will transmit sound well. Liquids and gases particles are not packed as tightly, therefore, the particles do not hit and vibrate from each other as well as solids and do not travel as efficiently and therefore transmit sound the most poorly. Reflection of light As light travels from water to air, it changes direction. Light normally travels in straight lines. However, under certain conditions, it is possible to change the direction of light. In the example below, the light has been bent. Light can be made to bend by passing it through different transparent media. This bending of light through different media is called refraction. When light travels from one transparent medium to another, it speeds up or slows down. For example, when light travels from air to water it slows down. When it travels from water to air, it speeds up. The bending of a light ray as it passes from one medium to another is caused by the light's change in speed. The speed of light through different media is given in the table right. The best way to describe which way the light bends is to draw a line at right angles to the boundary. This line is called the normal. When light speeds up, as it does when it passes from water into air, it bends away from the normal. When light slows down, as it does when it passes from air into water, it bends towards the normal.  Science Study The light coming from the swimmer's legs in the photograph above bends away from the normal as it emerges from the water into the air. The bending of light through transparent materials can be used to produce some interesting and useful effects. Lenses are useful because they bend light in a predictable way and can change the way we see the world. The type of image produced by a lens depends on the shape of the lens. Two basic shapes Lenses can be shaped in two basic ways; the ones that curve outwards are called convex lenses. Those that curve inwards are called concave lenses. Convex lenses are sometimes called converging lenses. That's because light rays that pass through them are refracted towards each other so that they meet (converge) at a point. The point where the light rays meet is called the focal point of the lens. Concave lenses are sometimes called diverging lenses. When rays of light pass through these lenses, they refract away (diverge) from each other. Concave lenses have no real focal point, because rays of light do not meet after passing through the lens. However, if you trace the rays back to where they appear to have come from, they do meet at a point, called a ‘virtual’ focal point. Reflection, refraction and absorption Reflection Reflection occurs when light hits the surface of an object and bounces off the object. The law of reflection states that the angle of incidence (the angle of incoming light) is equal to the angle of reflection (view diagram below). Reflection is used in everyday life to produce mirrors. Mirrors are important for cars to be able to see what is behind you or beside you when driving. Refraction Refraction is the bending of light as it passes from one transparent (see through) substance into another. This bending by refraction makes it possible for us to have lenses, magnifying glasses, prisms and rainbows. Even our eyes depend upon this bending of light. Without refraction, we wouldn’t be able to focus light onto our retina and SEE! This change of direction is caused by a change in speed. For example, when light travels from air into water, it slows down, causing it to continue to travel at a different angle or direction (bends). Absorption  Science Study Different forms/type of matter will absorb different wavelengths of light. When white light (made up of all colours) is shined onto an object, the colour that you see/perceive is the wavelengths of light that were reflected by that object. All the other wavelengths of light were absorbed by that object. An object that is black, does not reflect ANY wavelengths, an object that is white reflects ALL wavelengths. That is why black objects usually heat quicker when placed in the sun compared to white objects. Key areas to study Conduction the transfer of heat from a warmer object to a cooler one by direct contact Conductor a material that allows heat to flow through it easily; metals are good conductors of heat Convection the transfer of heat by the flow of a fluid from a warmer area to a cooler area Radiation the transfer of heat by electromagnetic waves Insulator a material that doesn't allow heat to flow through it easily; plastics, air, wood and cloth are good insulators Kinetic energy the energy a moving object has because of its motion absorption The transfer of light energy into an object Black objects absorb all frequencies of light. Blue objects absorb red, green and yellow light. colour A property of visible light that depends on its frequency The lowest frequency of light that we can see is red, and the highest is purple. concave lens A lens that is curved inwards and is thinner in the middle Concave lenses cause light rays to diverge and produce smaller images. converge To get closer together Convex lenses cause parallel light rays to converge. convex lens A lens that is curved outwards and is thicker in the middle Convex lenses cause light rays to converge and can produce either bigger or smaller images.  Science Study diverge To get further apart Concave lenses cause parallel light rays to diverge. focal length The distance between the centre of a lens and its focal point The focal length depends on how strongly the lens refracts light. focal point A place where light rays either converge to or diverge from The focal point is located behind a concave lens and in front of a convex lens. frequency The number of waves that go by in one second Frequency is measured in waves per second. Higher frequency waves have shorter wavelengths. lens A curved piece of transparent glass or plastic that refracts light Lenses have many useful applications, including glasses, cameras, microscopes and telescopes. light A type of energy that travels in electromagnetic waves Light energy allows us to see the world around us. It also provides plants with energy needed to make food by photosynthesis. magnification A measure of a lens's ability to increase the size of an image A magnifying glass with a magnification of 2x makes things appear two times larger than they really are. opaque Not allowing light to pass through Because light is absorbed by opaque materials, we cannot see through them. prism A transparent object with flat surfaces, which refract light Prisms demonstrate that white light is a mixture of all colours, which are refracted by different amounts. reflection The bending of light as it bounces off a surface White objects reflect all frequencies of light. Blue objects reflect mostly blue light. refraction The bending of light as it passes into a new material The refraction of light by lenses has many useful applications, such as cameras, microscopes and telescopes. translucent Allowing only some light to pass through Because only some light passes through translucent materials, objects appear blurred. transmission The passing of light through a material A window is made of glass that transmits light, allowing us to see through it. transparent Allowing nearly all light to pass through Because light passes through transparent materials, we can see through them clearly.  Science Study visible The range of light frequencies that we can see spectrum The visible spectrum includes all the colours of the rainbow. wave A repeated motion that transfers energy Unlike sound waves and ocean waves, light waves can travel through a vacuum. wavelength The distance between one crest of a wave and the next crest Different colours of light have different wavelengths. Red light has the longest wavelength in the visible spectrum. amplitude The distance between the midline of a wave and the top or bottom The amplitude of a sound wave relates to the amount of energy it transfers. compression Part of a sound wave where particles are closer together On a wave graph, a compression is represented by a high point, or crest. decibel A unit used to measure loudness A normal conversation has a loudness of about 60 dB. A jet plane taking off has a loudness of about 140 dB. frequency The number of waves that go by in one second The higher the frequency of a sound wave, the shorter its wavelength. hearing range The range of frequencies that can be heard by a human or animal Humans can hear sounds between about 20 Hz and 20,000 Hz. Other animals have different hearing ranges. hertz The standard unit of frequency Elephants communicate using very low frequencies that we can't hear. high-pitched The quality of sounds produced by waves with high frequency A small bell vibrates very quickly, producing a high-pitched note longitudinal A wave in which particles move back and forth in the wave direction wave Sound waves are longitudinal because the particles move back and forth in the same direction as the wave. loud The quality of sounds produced by waves with high amplitude Loud sounds involve sound waves with more energy that disturb the particles more. loudness A quality of sound that depends on the amplitude of the sound wave The greater the amplitude of a sound wave, the more energy it has and the louder it sounds. low-pitched The quality of sounds produced by waves with low frequency A large drum vibrates slowly, producing a deep, booming sound. medium A substance that a wave travels through Sound waves can only travel through a medium, such as air, water or steel.  Science Study pitch A quality of sound that depends on the frequency of the sound wave The higher the frequency of a sound wave, the higher it sounds. quiet The quality of sounds produced by waves with low amplitude Quiet sounds involve sound waves with less energy that disturb the particles less. rarefaction Part of a sound wave where particles are further apart On a wave graph, a rarefaction is represented by a low point, or trough. sound A type of energy transmitted by vibrating particles Sound can travel through solids, liquids and gases. It cannot travel through a vacuum, such as outer space. sound wave A vibration of particles that transfers energy Sound waves are produced by vibrating objects, such as a ringing bell or the vocal cords in someone's throat. transverse A wave in which particles move at right angles to the wave direction wave Ocean waves are transverse because the particles move up and down as the wave moves horizontally. wave A repeated motion that transfers energyWaves can take many different forms, including sound, light, earthquakes and ocean waves. Working Scienticially Variables Scientists use experiments to figure out how things work. They change one thing, called the independent variable, to see how it affects something else, called the dependent variable. For example, if you wanted to see how much water affects how fast a plant grows, the amount of water would be the independent variable, and the plant's growth would be the dependent variable. To make sure the experiment is fair, scientists keep everything else the same. These are called controlled variables. For example, in the plant experiment, you would want to make sure all the plants get the same amount of sunlight, the same type of soil, and the same amount of fertiliser. Scientists use these variables to ask questions and test their ideas. They might ask, "How does the amount of water affect how many days it takes for a tomato plant to flower?" Then, they would design an experiment to test their question. When scientists change the independent variable, they expect to see a change in the dependent variable. This is called the hypothesis. For example, the hypothesis for the plant experiment might be, "If I give one plant more water than another, then the plant with more water will flower sooner."  Science Study By carefully changing the independent variable and observing the dependent variable, scientists can learn about how things work. They can use this information to solve problems and make new discoveries. Validity, Reliability and Accuracy When scientists conduct experiments, they need to make sure their results are reliable, valid, and accurate. These terms might sound similar, but they mean different things. Reliability means that the results of an experiment are consistent. If you repeat the experiment several times, you should get similar results each time. Imagine you're trying to measure the height of a plant. If you measure it three times and get three different heights, your measurements are not reliable. Validity means that the experiment is actually measuring what it's supposed to measure. For example, if you're trying to measure the effect of sunlight on plant growth, you need to make sure that you're only changing the amount of sunlight the plant gets, and not other factors like the amount of water or the type of soil. If you change other things, your experiment won't be valid. Accuracy means that the results of the experiment are close to the true value. For example, if you're measuring the temperature of a room, your thermometer should be accurate, meaning it should show the correct temperature. If your thermometer is inaccurate, it might show a temperature that's too high or too low. It's important to remember that an experiment can be reliable without being accurate. For example, if you use a broken thermometer to measure the temperature of a room, you might get the same reading every time, but the reading will be wrong. This means your measurements are reliable, but not accurate. Scientists use these terms to make sure their experiments are well-designed and their results are trustworthy. By understanding the difference between reliability, validity, and accuracy, you can better understand the scientific process and the importance of careful experimentation.