1. Test Review Chapters 12-16 Relativity

2. Question #1 What happens to the gravitational force when 2 objects get farther away from each other?

3. It decreases!

4. Question #2 A 35 kg rock and a 250 kg rock are placed 17 m apart. What is the gravitational force between them?

6. Question #3 How fast must a spaceship travel to be able to leave the earth’s gravitational pull?

7. 8 km/s

8. Question #4 How long does it take light from the sun to travel to Earth?

9. 8 minutes

10. Question #5 How much energy is contained within a T-84 calculator with a mass of 0.89 kg?

12. Question #6 The sun exerts a 3.5 x 10 22 N force on the earth. What is the distance between the 1.99 x 10 30 kg sun and the 5.97 x 10 24 kg Earth?

14. Question 7 In Feb. 2007, the Hubble Telescope captured pictures of a dying star with a mass of 2.0 x 10 30 kg.. If this star was 4,200 light years away, how long ago did the star die?

15. ~ 4,200 years ago

16. Question #8 At what point during the planet’s orbit around the sun does it have the least amount of velocity?

17. S

18. Question #9 What is the speed of light? (in m/s) ?

19. 3.00 x 10 8 m/s

20. Question #10 What is the gravitational force between a 7.5 x 10 5 kg object and a 2.50 x 10 8 kg object that are 2.5 x 10 11 m apart?

22. Question #11 2 objects are attracted to each other. What happens to their speed as they get closer?

23. It increases!

24. Question #12 What were black holes before they became black holes?

25. Stars!

26. Question #13 Name 2 points during the planet’s orbit around the sun where it has the same amount of velocity.

27. All below are correct… P & V Q & U R & T

28. Question #14 If our sun were to become a black hole tomorrow, what would happen to the earth’s orbit around the sun?

29. Nothing. …because our orbit is due to the gravitation between the sun & the earth, and that didn’t change simply because the sun became a black hole. A black hole is the same mass, but in a much smaller package!

30. The end.