Answer Key to Phys 11 Self test (prelim cov)

Answer Key
I. Multiple choices (2 pts each)
1. A
2. D
3. B
4. B
5. B

6. A
7. A
8. D
9. E
10. B

11. C
12. C
13. B
14. B
15. D

16. D
17. E
18. C
19. A
20. A

21. C
22. D
23. C
24. B
25. B


II. PROBLEMS’ FINAL ANSWERS (10 pts each)
1. (b) Rx = -1618.05 km
Ry = 801.72 km
R=1805.78 km
Direction: 26.36 degrees North of West
2. (a) 21.28 m
(b) 20.64 m/s

3. (c) 0.49 m/s^2
4. vx = -19.67 km/h
vy = 6.89 km/h
v = 20.84 km/h
direction: 19.30 degress North of West

5. (a) v = 2.99 x 10^4 m/s
(b) Equate the centripetal force to the gravitational force exerted by the Sun on the Earth. Your equation should look like this
mv^2/R=GmM/R^2
Where M is the Sun’s mass, m is the mass of the earth, and R is the radius of Earth’s orbit.
M = 2.01 x 10^30 kg