Please answer ALL questions as this is very important.

1. A car starts from City A, goes 60 km in a straight line to City B, immediately turns around, and returns to City A. The time for this round trip is 3 hours. The average speed of the car for this round trip is:

a. 120 km/h

b. 10 km/h

c. 40 km/h

d. 0 km/h

e. 20 km/h

2. At time t = 0, a car has a velocity of 16 m/s. The breaks are applied so the car decelerates at 2 m/s². The car will stop after:

a. 16 s

b. 32 s

c. 8 s

d. 2 s

3. (Ignore the units in this question.) The position of an object at time t is given by:

x = 12 - 4t²

Compare this formula to the one for motion with constant acceleration and determine the object's acceleration. Select the correct answer among the following:

a. 8

b. - 8

c. - 4

d. 4

4. If an elevator is ascending toward the top floor of a building and slowing down, then its:

a. velocity points downward and its acceleration points downward.

b. velocity points upward and its acceleration points downward.

c. velocity points upward and its acceleration points upward.

d. velocity points downward and its acceleration points upward.

5. A feather and a bowling ball are dropped from rest in a vacuum on the moon. The acceleration of the feather is:

a. less than that of the bowling ball.

b. the same as that of the bowling ball.

c. zero since it floats in the vacuum

d. 9.8 m/s²

e. more than that of the bowling ball.

6. A boy is throwing a dart toward a dart board that's a few meters away. He throws the dart at an angle (not horizontally) and the dart hits the board at the same height at which it was thrown. Neglect air resistance. Compare the magnitudes and directions of the dart's vertical velocity components at its initial and final positions.

a. The magnitudes of the vertical components are the same, but their directions are opposite.

b. The initial vertical component is smaller than the final vertical component and the components are in the opposite directions.

c. The initial vertical component is greater than the final vertical component and the components are in the opposite directions.

d. The initial vertical component is greater than the final vertical component and they are in the same direction.

e. The magnitudes and directions of the vertical components are the same.

7. While a cargo plane is simultaneously ascending 12 m per second and flying due south at 150 km/h, an object is dropped from it. Take that the acceleration due to gravity is 9.8 m/s² and that there is no air resistance. After 2 seconds of falling, the object's acceleration is:

a. 44 m/s² downward

b. 31 m/s², pointing between up and south

c. 9.8 m/s² downward

d. 58 m/s², pointing between down and south

8. The distance between buildings A and B is 300 m. A car passes building A at a speed of 12 m/s and heads toward building B along a straight line with constant acceleration. The car reaches building B in 10 s. The acceleration of the car is:

a. 0.28 m/s²

b. 7.1 m/s²

c. 1.8 m/s²

d. 3.6 m/s²

9. The mass of a rock on the Earth is 4 kg. The rock is then taken to the Moon. What is the weight of the rock on the moon if the acceleration due to gravity is 1.6 m/s²?

a. 6.4 N

b. 0.4 N

c. 2.5 N

d. 4 N

10. When a certain force is applied to a 2-kg object its acceleration is 4 m/s². When the same force is applied to another object its acceleration is 4 times as much. The mass of the second object is:

a. 2 kg

b. 8 kg

c. 0.5 kg

d. 1 kg

11. A jug of milk rests on top of a magazineon a table. You hold onto the edge of the magazine and jerk it away quickly from under the jug. The jug doesn't topple because

a. the jug has inertia.

b. the jug has weight.

c. there is an action-reaction pair of forces on the jug.

d. gravity tends to hold the jug secure.

12. An object weighs 108 N when at distance R from the center of the Earth. Its weight at distance 3R from the center of Earth is:

a. 324 N

b. 12 N

c. 36 N

d. 108 N

13. Which of the following objects has the greatest kinetic energy?

a. a 2-kg object moving at 2 m/s

b. a 2-kg object moving at 3 m/s

c. a 1-kg object moving at 5 m/s

d. a 4-kg object moving at 2 m/s

14. A piece of debris is motionless in outer space.Asecondpiece of debris with 3 times the mass moving at 12 m/s collides with it. The pieces get stuck together and move with a common speed of:

a. 6 m/s

b. 9 m/s

c. 4 m/s

d. 3 m/s