PHYSICS 321 - Classical Mechanics I

Spring 2010

Homework Set #9 (due 4/7/10)

1. Thornton and Marion, problem 8-6. (a) Use conservation of momentum and energy.

(b) Subsequently, get the same answers using the concept of reduced mass.

2. Thornton and Marion, problem 8-9.

3. Thornton and Marion, problem 8-10. Hint: Calculate the total energy for the Earth’s orbit both before and after the Sun loses half of its mass.

4. Thornton and Marion, problem 8-17.

5. Thornton and Marion, problem 8-21.

6. Thornton and Marion, problem 8-5. Hint: First use Newton’s 2^nd Law to calculate the period of the circular orbit. Then consider what happens after the particles are stopped. Use conservation of energy to give v = r-dot = dr/dt. Then you need to integrate this to find the time until the particles collide. After a variable change r = y², the integral will be of the form of Eq. E.7 in Appendix E. Good luck!