PRACTICE QUIZ 8A

Answer the following questions completely and clearly.

1. How does the speed of an orbiting body (planet, comet, etc.) change as the body moves through its orbit?

 

 

2. What is the mathematical relationship between gravitational attraction and distance of separation between two objects?

 

3. What is important about the work done by Cavendish?

 

4. According to Einstein, what do objects do which causes them to "gravitate?"

 

5. State Kepler's Laws of Planetary Motion.

 

 

 

 

6. In what ways is a gravitational field different from other fields (like electric and magnetic fields)?

 

7. Why can't our Sun become a black hole?

 

8. Classical physics cannot explain phenomena at the center of a black hole. What rules govern events at the singularity?

   

Solve the following. Show all work and circle your answer.

9. Calculate the attraction (gravitational, that is) between a 50.0 kg girl and a 60.0 kg boy if their centers of mass are 2.50 m apart in physics class? (answer = 3.20 x 10^-8 N)

 

 

 

10. The asteroid Icarus, though only a few hundred meters across, orbits the sun like any of the planets. Its period is about 410 days. What is its average distance from the sun? (answer = 1.6 x 10¹¹ m)