1. 9/21/2012PHY 113 A Fall 2012 -- Lecture 101 PHY 113 A General Physics I 9-9:50 AM MWF Olin 101 Plan for Lecture 10: Chapter 6 -- Newton’s Laws continued 1.Newton’s Laws and centripetal acceleration 2.Newton’s Laws and resistive forces

2. 9/21/2012 PHY 113 A Fall 2012 -- Lecture 102

3. 9/21/2012PHY 113 A Fall 2012 -- Lecture 103 iclicker exercise: Exam feedback: A.Too hard B.Too easy C.Neutral

4. 9/10/2012PHY 113 A Fall 2012 -- Lecture 64 Recall: Uniform circular motion: animation from http://mathworld.wolfram.com/UniformCircularMotion.html http://mathworld.wolfram.com/UniformCircularMotion.html

5. 9/10/2012PHY 113 A Fall 2012 -- Lecture 65 Uniform circular motion – continued

6. 9/10/2012PHY 113 A Fall 2012 -- Lecture 66 Uniform circular motion – continued r In terms of time period T for one cycle: In terms of the frequency f of complete cycles:

7. 9/10/2012PHY 113 A Fall 2012 -- Lecture 67 Uniform circular motion and Newton’s second law r iclicker exercise: For uniform circular motion A.Newton’s laws are repealed B.There is a force pointing radially outward from the circle C.There is a force pointing radially inward to the circle

8. 9/21/2012PHY 113 A Fall 2012 -- Lecture 108 http://earthobservatory.nasa.gov/Features/OrbitsCatalog/page1.php Example of uniform circular motion:

9. 9/21/2012PHY 113 A Fall 2012 -- Lecture 109 Example of uniform circular motion: Consider the moon in orbit about the Earth

10. 9/21/2012PHY 113 A Fall 2012 -- Lecture 1010 Example of uniform circular motion:

11. 9/21/2012PHY 113 A Fall 2012 -- Lecture 1011 Example of uniform circular motion:

12. 9/21/2012PHY 113 A Fall 2012 -- Lecture 1012 Curved road continued:

13. 9/21/2012PHY 113 A Fall 2012 -- Lecture 1013 Mass on a swing: mg  T iclicker exercise: Which of these statements about the tension T in the rope is true? A.T is the same for all . B.T is smallest for  C.T is largest for  L

14. 9/21/2012PHY 113 A Fall 2012 -- Lecture 1014 Newton’s law in accelerating train car

15. 9/21/2012PHY 113 A Fall 2012 -- Lecture 1015 Models of air friction forces mg bv