General Physics 1, 1st Quarter: Week 1 PDF

General Physics 1 1 st Quarter: Week 1 The Great Chain Race Form 5 groups Materials: Ruler Colored Paper UNIT 1: UNITS OF MEASUREMENT Essential Questions: 1. Why do we measure things? 2. Why is it important to have a standard system of measurement?...

General Physics 1 1 st Quarter: Week 1 The Great Chain Race Form 5 groups Materials: Ruler Colored Paper UNIT 1: UNITS OF MEASUREMENT Essential Questions: 1. Why do we measure things? 2. Why is it important to have a standard system of measurement?  Learning Goals Explain the importance of a standard system of measurement. Discuss SI units. Solve problems involving conversion of units. Cite importance of measurement in everyday living. How do we measure? Measurement In the past, Egyptians and Babylonians use their body parts to estimate the length of an object. It is a process of assigning a quantity to describe a property of an object by comparing it with a standard. METRIC SYSTEM International or SI  What is the Metric System? It is the standard system of measurement for the fundamental quantities abbreviated from Système International. It is established in 1960. The 7 Fundamental Quantities And Its Si Base Units QUANTITY SYMBOL UNIT SYMBOL TIME 𝑡 𝑠𝑒𝑐𝑜𝑛𝑑 𝑠 LENGTH 𝑙 𝑚𝑒𝑡𝑒𝑟 𝑚 MASS 𝑚 𝑘𝑖𝑙𝑜𝑔𝑟𝑎𝑚 𝑘𝑔 ELECTRIC CURRENT 𝐼 𝐴𝑚𝑝𝑒𝑟𝑒 𝐴 TEMPERATURE 𝑇 𝐾𝑒𝑙𝑣𝑖𝑛 𝐾 AMOUNT OF SUBSTANCE 𝑛 𝑚𝑜𝑙𝑒 𝑚𝑜𝑙 LUMINOUS INTENSITY 𝐼𝑣 𝑐𝑎𝑛𝑑𝑒𝑙𝑎 𝑐𝑑  How do you express very small or very large quantities? Prefixes used with SI units Prefixes are added to the base units to make the value of the unit smaller or larger. Conversion of Units (Metric Prefixes) 1. 𝟐𝟑𝟕𝟖𝟎 𝒎𝒎 → 𝒌𝒎 𝟏 𝒎𝒎 = 𝟏𝟎−𝟔 𝒌𝒎 −𝟔 𝟒 𝟏𝟎 𝒌𝒎 −𝟐 𝟐. 𝟒 𝒙 𝟏𝟎 𝒎𝒎 𝒙 = 𝟐. 𝟒 𝒙 𝟏𝟎 𝒌𝒎 𝟏 𝒎𝒎 𝟏 𝒌𝒎 = 𝟏𝟎𝟔 𝒎𝒎 𝟒 𝟏 𝒌𝒎 = 𝟐. 𝟒 𝒙 𝟏𝟎 −𝟐 𝒌𝒎 𝟐. 𝟒 𝒙 𝟏𝟎 𝒎𝒎 𝒙 𝟏𝟎−𝟔 𝒎𝒎 Conversion of Units (Metric Prefixes) 2. 𝟒𝟖. 𝟗 𝑷𝒈 → 𝝁𝒈 𝟐𝟏 𝟏 𝑷𝒈 = 𝟏𝟎 𝝁𝒈 𝟐𝟏 𝟏𝟎 𝝁𝒈 𝟐𝟐 𝟒. 𝟗 𝒙 𝟏𝟎𝟏 𝑷𝒈 𝒙 = 𝟒. 𝟗 𝒙 𝟏𝟎 𝝁𝒈 𝟏 𝑷𝒈  Derived Quantities These are based on the seven fundamental quantities and are expressed from the product of two or more base units.  Derived Units Derived Derived unit in Special Name Symbol Quantity terms of base units volume V m3 speed, velocity v m s–1 force newton N kg m s–2  Derived Units Derived Derived unit in terms Special Name Symbol Quantity of base units energy, work joule J kg m2 s–2 or N m heat capacity J/K kg m2 s–2 K–1 electric charge coulomb C As  Other System of Measurement The British Imperial system or imperial units are used limitedly in some countries. It was established from the Weights and Measures Act of 1824 and was continuously reformed. While the British continue to refine their measurement, the Americans adopted the units from the act of 1824 and called it the U.S. customary units.  Other System of Measurement Examples of Imperial and U.S. Customary Units with their Metric Equivalent Unit Abbreviation Metric Equivalent pound lb 4.448 N slug slug 14.59 kg ounce oz 28.350 grams  Other System of Measurement Examples of Imperial and U.S. Customary Units with their Metric Equivalent Unit Abbreviation Metric Equivalent mile mi 1 609 m or 1.609 km foot ft 30.48 cm inch in 2.54 cm  Conversion of Units 1. 𝟔 𝒎𝒊𝒍𝒆𝒔 → 𝒊𝒏𝒄𝒉𝒆𝒔 𝟏𝟔𝟎𝟗 𝒎 𝟏𝟎𝟎 𝒄𝒎 𝟏 𝒊𝒏𝒄𝒉 𝟔 𝒎𝒊𝒍𝒆𝒔 𝒙 𝒙 𝒙 𝟏 𝒎𝒊𝒍𝒆𝒔 𝟏𝒎 𝟐. 𝟓𝟒 𝒄𝒎 = 𝟑𝟖𝟎𝟎𝟕𝟖 𝒊𝒏𝒄𝒉𝒆𝒔  Conversion of Units 2. 𝟒 𝒔𝒍𝒖𝒈𝒔 → 𝒐𝒛 𝟏𝟒. 𝟓𝟗 𝒌𝒈 𝟏𝟎𝟎𝟎 𝒈 𝟏 𝒐𝒛 𝟒 𝒔𝒍𝒖𝒈𝒔 𝒙 𝒙 𝒙 𝟏 𝒔𝒍𝒖𝒈 𝟏 𝒌𝒈 𝟐𝟖. 𝟑𝟓𝟎 𝒈 = 𝟐𝟎𝟓𝟖. 𝟓𝟓 𝒐𝒛  REMEMBER! Most of the quantities in examples and problems require the use of SI units. The Imperial and U.S. customary units may be occasionally mentioned but use the SI units as much as you can.  Why is it important to convert units?  Conversion of Units An equation or expression should always be consistent with the units to correctly solve it. Units can be treated as algebraic quantities that can cancel each other.  Conceptual Questions 1. Cite some practical applications of measurements. 2. Why is it important to have a standard system of measurement? General Physics 1 1 st Quarter: Week 1  Let’s Recall! 1. How do you express very small or very large quantities? 2. What are the 7 fundamental quantities and its base units?  Pass the Number! PROCEDURES: 1. The teacher will give a quantity to all the first students in each group at the same time. 2. The first person in the line whispers the number to the next person.  Pass the Number! PROCEDURES: 3. All players whisper the number to the next person until it reaches the last person in line. 4. The last player writes the original form of the number on the board. Students are not allowed to use any shortcuts or shorthand notation. UNIT 1: Scientific Notation  Learning Goals Discuss the importance of scientific notation and significant figures. Write measurements in scientific notation and the correct number of significant figures. Solve measurement problems using scientific notation and express answers in the correct number of significant figures. Scientific Notation All numbers can be expressed using the form: Equation 1.1  Addition and Subtraction in Scientific Notation To add and subtract quantities in scientific notation, you need to make sure first that the expressions have similar terms.  Addition and Subtraction in Scientific Notation 1. Suppose you are required to add the following masses: 5.5 ✕ 103 kg and 3.6 ✕ 103 kg. 2. Add the masses of the two vehicles 5.5 ✕ 103 kg and 3.6 ✕ 105 kg.  Addition and Subtraction in Scientific Notation Subtraction of quantities in scientific notation follows the same rules as addition. The powers of ten should have the same exponents before factoring it out and subtracting N accordingly. Let’s Practice! 1. Magaling, Malingap, and Masipag are three adjacent barangays. Brgy. Magaling is 7.0 ✕ 103 m away from Brgy. Malingap. On the other hand, the distance between Brgy. Malingap to Brgy. Masipag is 1.2 ✕ 103 m. What is the total distance between Brgy. Magaling and Brgy. Masipag? Let’s Practice! 2. Leo stored water in two large containers containing 2.50 ✕ 104 mL and 5.10 ✕ 104 mL. He used 3.00 ✕ 104 mL to wash the dishes and clean the kitchen countertop. How much water was left for his consumption?  Multiplication and Division in Scientific Notation To multiply quantities in scientific notation, N and a are calculated separately. N are multiplied to one another while the exponents, a, are added.  Multiplication and Division in Scientific Notation 1. Suppose you are asked to calculate the area of a field with dimensions of 1.5 ✕ 102 m and 2.1 ✕ 104 m. 2. Suppose you are asked to divide 2.1 ✕ 104 m by 1.5 ✕ 102 m. Let’s Practice! 1. Calculate the floor area of a large conference hall with a width of 4.20 ✕ 102 m and a length of 9.50 ✕ 102 m. 2. How many 1.50 ✕ 102-cm long sticks fit in an 870 ✕ 102-cm long space? Seatwork 1: 1. (2.56 X 103) + (6.964 X 103) 2. (9.49 X 105) – (4.863 X 105) 3. (4.12 x 106) + (3.94 x 104) 4. (4.23 x 103) – (9.56 x 102) 5. (2.46 X 106) + (3.4 X 103) Seatwork 1: 6. (5.60×102)×(7.102×104) 7. (3.04×105)÷(9.89×102) 8. (3𝑥108 )(6.8𝑥10−13 ) 9. (8.2𝑥106 )(1.5𝑥10−3 )(1.5𝑥10−7 ) (2.829𝑥10−9 ) 10. (3.45𝑥10−3 ) General Physics 1 1 st Quarter: Week 1 UNIT 1: Significant Figures  Learning Goals Discuss the importance of scientific notation and significant figures. Write measurements in scientific notation and the correct number of significant figures. Solve measurement problems using scientific notation and express answers in the correct number of significant figures. Significant Figures Nonzero digits are always significant. Zeros between nonzero digits are considered significant. Only the final zero and trailing zeros following a decimal point are considered significant. Zeros that appear before the nonzero digit are not significant. Significant Figures 1. 9500.23 N 2. 0.0145000 m3 3. 1 020 g/cm3 4. 11 070 250 km 5. 0.0000006750 Significant Figures in Addition and Subtraction The number of significant figures in the sum or difference is the same as that of the least accurate measurement. The final answer must contain the same number of decimal places as the least accurate measurement. Least accurate measurement refers to the quantity with the least number of decimal places. Let’s Practice! 1. What is the sum of 90 cm and 21.5 cm using the correct significant figures? 2. A student measured the height of her three plants. She got 9.2 cm, 10 cm, and 5.22 cm. What is the total length of all the plants?  Significant Figures in Multiplication and Division The final answer must contain the same number of significant figures as the least accurate measurement. Least accurate measurement refers to the quantity with the least number of significant figures. Let’s Practice! 1. During a physics experiment, a student multiplied the mass of an object with its acceleration to get the force. What would be the force if the mass of the object is 0.250 kg while its acceleration is 0.012 m/s2?  Assignment 1: I. Write true if the statement is correct. Otherwise, write false. 1. Very large and very small numbers are expressed using significant figures. 2. Scientific notation ensures that values are reported accurately based on the capability of the measuring device. 3. All expressions should have similar terms first before adding or subtracting numbers in scientific notation. 4. In the standard form of scientific notation, N can be any number between 1 to 100.  Assignment 1: II. Answer the following problems. 5. A student measured the height of her three plants. She got 9.2 cm, 10 cm, and 5.22 cm. What is the total length of all the plants? Write your answer in correct number of sig. figures. 6. Suppose you were asked by your teacher to measure the length of your book. Your classmate reported it to be a 15.679 cm. Would you believe the measurement of your classmate if he only used a ruler to measure it?