MEASUREMENTS CONVERSION AND SCIENTIFIC NOTATION.pptx

Ppt for students

1. Measurements Conversion and Scientific Notation Prepared by: Lordel L. Segovia

2. What is Physics?

3. Physics the study of matter, motion, energy, and force. is one of the most fundamental of the sciences. is an experimental science .

4. Common Research Facilities The Large Hadron Collider (LHC) in Geneva, Switzerland, Leaning Tower in Pisa, Italy,

5. Galileo’s theory has a range of validity

6. Measurement Is the process and skill of finding the dimension of physical quantity. A fixed quantity with respect to which a physical quantity is measured is called a unit .

7. Systems of Measurement 1. Metric System (e.g. m, km) 2. English System (e.g. in, ft)

8. Can we add 10 km and 500 m right away?

9. Conversion of Units One quantity must be changed its unit first following the unit of the other quantity. The value or magnitude of the physical quantity does not change, only the unit is changed.

10. Conversion Factors Distance 1 cm =10 mm 1 m = 3.28 ft = 39.37 in 1 km = 1000 m = 3280.84 ft 1 mi = 5280 ft = 1.609 km 1 ft = 12 in = 30.48 cm 1 in = 2.54 cm

11. Conversion Factors Mass 1 kg = 1000 g 1 slug = 14 600 g = 14.6 kg 1 metric ton = 1000 kg Time 1 hr = 60 min = 3600 s 1 day = 24 hr = 1440 min = 86 400 s 1 yr = 365 days 1 min = 60 s

12. Conversion Factors Area 1 Power 1 hp = 746 W = 550 ft. lbs 1 MW = 1000 W 1 GW = 1 000 000 W  

13. Conversion Factors Volume Force 1 N = 100000 dynes 1 lb = 4.45 N 1 kg mass = 2.2 lb  

14. Conversion Factors Pressure 1 torr 1 mm Hg = 133 Pa 1 bar = 100 000 Pa 1 atm = 14.7 psi = 101 300 Pa = 76 cm Hg = 760 torr = 760 mm Hg  

15. Conversion Factors Angle 1 rev = 360 = Energy 1 cal = 4.186 J  

16. Time (second) 1889 – 1967, time was defined as a certain fraction of the mean solar day Present standard (1967) energy difference between two cesium atom 1 sec = 9,192, 631, 770 cycles of microwave radiation

17. Length (meter) (1960) Wavelength of the orange-red light emitted by atoms of Krypton (86Kr) in a glow discharge tube definition of the meter (abbreviated m) is the distance that light travels in vacuum in 1/299,792,458 second

18. Mass (kilogram) Defined to be the mass of a particular cylinder platinum – iridium alloy kept at the international Bureau of Weights and Measures at Sèvres , near Paris

19. Scientific Notation 1 980 000 000 000 000 000 000 000 000 000 Kg Mass of an electron 0.000 000 000 000 000 000 000 000 000 000 91 Kg

20. Scientific Notation Is a shorthand for writing very large or very small numbers. A number is said to be in scientific notation, if it is written as a product of a number equal or greater than one but less than 10, and a power 10. A number in scientific notation has three parts: coefficient, the base, and the exponent.

21. Conversion of Units 60 MW to W 200 Pa to atm 32.08 Kg to g The world land speed record is 763.0 mi/h, set on October 15, 1997, by Andy Green in the jet-engine car Thrust SSC. Express this speed in meters per second. Hint: 1 mi = 1.609 km The world’s largest cut diamond is the First Star of Africa (mounted in the British Royal Sceptre and kept in the Tower of London). Its volume is 1.84 cubic inches. What is its volume in cubic centimeters? In cubic meters? Hint: 1 in. = 2.54 cm  

22. Scientific Notation Convert the following numbers in ordinary notation to standard scientific notation. 490 000 000 1 230 000 000 50 500 000 0.000 000 097 0.000 0212 0.000 000 00730

23. Rules of Significant Figures Zeroes between non zero digits are significant. Example: 1. 3,091 = 4 4. 500603 = 2. 82, 024 = 3. 109,003 =

24. 2. Zeroes that come before all non-zero digits are never significant Example: 1. 0.000491 = 3 2. 0.0132 = 3. 0.000000062 =

25. 3 . Trailing zeros for a number that ends with a decimal point are significant Example: 1. 83,000. = 5 2. 83.=2 3. 789.= 4. 90,000. = 5. 200. = 6. 50. =

26. 4. Trailing zeros to the right of the decimal place are significant. Example: 1. 83.000 = 5 2. 4,532.00 = 3. 789.000 = 4. 90.000 = 5. 200.00 = 6. 50.000 =

27. 5. Exact number, and irrationally defined numbers like Euler’s number (e), and pi ( , have an infinite number of significant figures. Example: 2. 1 m = 100 cm 3. speed of light = 299,792, 458 m/s  

28. 6. For any value written in scientific notation as , the number of significant figures is determined by applying the above rules only to the value of A; the x is considered an exact number and thus has an infinite number of significant figures. Ex.4500 can written in scientific notation to reflect two, three and four significant figures.  

29. Practice 1. 10082 = 2. 70,000,000. = 3. 0.00008914 = 4. 3,008,000 = 5. 70,000,000 = 6. 0.0025 = 7. 84.10000 = 8. 0.000339 =

30. Calculations with significant figures. For calculations involving measured quantities, the first step in determining the precision of the answer is to determine the number of significant figures in each of the measured quantities. Once done, the number of significant figures in a calculated value involving measurement is determined based on the mathematical operation being performed.

31. Calculations with significant figures 1. When two or more measured quantities are added or subtracted, the resulting value will have the same number of decimal places as the value with fewest number of decimal places (limiting value) Ex.  

32. Calculations with significant figures 2. When two or more measured quantities are being multiplied or divided, the answer will have the same number of total significant figures as the value with the fewest number of significant figures. Ex.  

33. Rules in rounding off: 1. When the digit to the right of the one being rounded to is less than a 5, the remaining digit remains the same as the value rounds down. Ex. 33.742 = round off to one decimal place =33.7

34. Rules in rounding off: 2. When the digit to the right of the one being rounded to is greater than, 5 the value rounds up. Ex. 2.8763 = to be rounded up to two decimal places. =2.88

35. Multiplication and Division with Significant Figures 1. 8.000 / 532 = 0.015037594 = 0.0150 2 . 480.00 / 23,000 =0.0208695652 = 0.021

36. Addition and Subtraction with significant figures 1.) 13.0198 + 1.2 = 14.2198 = 14.2 2.) 59.21 – 18.8722 =40.3378 = 40.34 3.) 8.679 +0.3 + 5.88 = 14.859 =14.9

37. Knowledge Check 1 Whole 1. What is physics? 2. What is the essence of measurement? 3. Define conversion of units and scientific notation. 4. Draw at least 10 applications of physics.