3. What is Physics ?

4. Questions not answered by physics: Physics answers the question:

5. How Things Work

6. Creativity in Physics How you can determine the height of a tall building with the use of a barometer? H S s h H

7. Creativity in Physics cont) There are many ways to determine the height of a tall building with the use of a barometer!

8. Models in Physics 8,000 mi

9. 1

10. Significant Digits 89 ABCD A = B = C = D =

11. Significant Digits 2 - Scientific Notation (Powers of Ten) How many significant digits in the measurement2000 meters ? Which of the following numbers is most accurate? 21 2.1.021 I will bet you that I can determine your height to 3 decimal place accuracy without using any instrument other than my eye, provided you are less than 6 ft, 6 in tall.

12. Significant Digits 3 W L T L = 4.71 cm W = 3.25 cm T =.25 cm The result of a calculation (multiplication or division) using measurements may not have more significant digits than the least accurate measurement used in the calculation.

13. Significant Digits 4 BA A = 104 cm B = 3.1 cm C =.25 cm D = A + B + C The result of a calculation (addition or subtraction) using measurements should be rounded to the smallest number of decimal places of any term in the sum. C

14. % Error NS NS = Standard Value (Accepted Value) NE NE = Experimental Value (Measurement) % Error = [(N S – N E )/ N S ] x 100 NS NS = NE NE =

15. % Error (cont.) % Error = [(N S – N E )/ N S ] x 100 Suppose you count 10 coins and error by 1. Suppose you count 100 coins and error by 1. Suppose you count 1000 coins and error by 1. Suppose you count 10000 coins and error by 1. The larger the number measured, the smaller the percent error. In measuring the distance from the Earth to the Moon (240,000 mi) you error by 1 mi. What is your % error?

16. Math in Physics Algebra, Geometry, Trig, Calculus Trig Functions – sine, cosine, tangent Calculus – simple differentiation and integration y = f(x) x y x1x1 x2x2 x3x3 x y x1x1 x2x2

17. Math in Physics – Linear Functions y = f(x) x y b A1A1 A2A2