11. How does the force of impact during a collision change when the time of contact is reduced?
A. It increases.
B. It decreases.
C. It instantaneously becomes zero.
D. It remains the same.
12. The threads of a screw used to fasten two pieces of wood are pitched at an angle. How does this increase the static friction force?
A. By increasing the normal force exerted by the wood on the screw thread
B. By increasing the ease of inserting the screw into the wood
C. By decreasing the coefficient of static friction between the screw and the wood
D. By decreasing the surface area between the screw surface and the wood
13. A 60 kg skier with an initial velocity of 12 m/s coasts up a hill. At the top of the hill, the skier is traveling at 9.75 m/s. Assuming there is no friction in the skis, how high was the hill?
A. 10 m
B. 0.25 m
C. 7.35 m
D. 2.5 m
14. A 1,500 kg car’s speed changes from 30 m/s to 15 m/s after the brakes are applied. Calculate the work done onto the car from the brakes.
A. −168,750 J
B. 506,250 J
C. −506,250 J
D. 168,750 J
15. What is true about weather?
A. The weather depends on so many conditions that it is not possible to account for them all in any model.
B. Accuracy increases the farther you are from the day’s weather you are predicting.
C. Weather can be predicted dependably by computational models.
D. The weather behaves randomly, which is why weather predictions are so often inaccurate.
16. Attached
17. Newton’s cradle is a contraption where metal balls hang from a frame. When one ball is pulled and released, the collision causes one ball on the opposite end to be released.
Which type of force can decrease the total momentum of this system?
A. friction force
B. strong nuclear force
C. magnetic force
D. electrostatic force
18. In a closed system, an object with a mass of 10 kg moves at a velocity of 5.4 m/s. It collides with a second object that has a mass of 12 kg and that is moving in the opposite direction with a velocity of 3.5 m/s. What is the total momentum of the system after the collision?
A. 42 kg-m/s
B. 66 kg-m/s
C. 54 kg-m/s
D. 12 kg-m/s
19. Attached
20. A wedge is a simple machine that is essentially two inclined planes. It is used to separate objects, such as in the head of an axe. The mechanical advantage of a wedge is given by MA = Lt, where L is the length of the wedge and t is the thickness. Which of these designs produces the highest mechanical advantage?
A. A length of 5 in. and a thickness of 5 in.
B. A length of 16 in. and a thickness of 4 in.
C. A length of 6 in. and a thickness of 2 in.
D. A length of 12 in. and a thickness of 2 in.
21. Object A and Object B are at equal distances on opposite sides of Object C. Object B has three times the mass of Object C. Objects A and B have equal mass. What is the ratio of the gravitational force between Objects A and B to the gravitational force between Objects B and C?
A. 3
B. 3/2
C. 2
D. 3/4
22. A geosynchronous satellite has an orbital period of 24 hours so that it stays fixed at a point above Earth’s surface. How far away does a geosynchronous satellite need to be from the surface of Earth, in kilometers?
A. 29,500 km
B. can be at any distance
C. 42,300 km
D. 35,900 km
23. Calculate the eccentricity for the planet if the distance between foci is 5,000,000 km and the distance of the major axis is 299,000,000 km.
A. 0.167
B. 0.598
C. 0.0167
D. 59.8
24. A planet travels in its orbit close to apogee, and in 2 years, its radius vector sweeps out an area of 3 A. How long will it take the planet’s radius vector to sweep an area of 3 A when it is close to perigee?
A. a larger time because the planet’s orbital speed will increase
B. a smaller time because the planet’s orbital speed will increase
C. a smaller time because the planet’s orbital speed will decrease
D. the same amount of time
25. If astronomers discovered a new planet and found its period of rotation around the Sun to be 105 years, how long would its semi-major axis length be as it orbited the Sun in AU?
A. 1.84 AU
B. 4.7 AU
C. 22.3 AU
D. 105 AU
Thank you! <3
