1. A mass of 5.25-kg was dropped from a height of 31 m. How much time does it take for the mass to reach the ground?

a. 9.8 seconds

b. 4.5 seconds

c. 4.0 seconds

*d. 2.5 seconds

2. A rocket is accelerating at a constant rate of 30 m/s².How much time does it take for the rocket to increase its speed from 3000 m/s to 3600 m/s?

*a. 20 s

b. 120 s

c. 200 s

d. 12 s

3. The position of a ball is given by x(t) = 30t - 3.0t². At what time is the ball stopped?

a. 1.0 s

*b. 5.0 s

c. 6.0 s

d. 9.0 s

4. A rocket starts from rest and reaches a speed of 250 m/s in 5 s. What is its average acceleration?

a. 9.8 m/s²

b. 245 m/s²

*c. 50 m/s²

d. 1250 m/s²

5. A motorcycle increases its speed from 5 m/s to 45 m/s over a distance of 55 m. How long does this take? Assume that the acceleration is constant.

a. 1.0 s

b. 5.5 s

c. 22.5 s

*d. 2.2 s

e. Not enough information

6. A truck is stopped in 9.3 seconds from an initial speed of 16 m/s. What is the acceleration of the car?

*a. -1.72 m/s²

b. -17.2 m/s²

c. 1.72 m/s²

d. 17.2 m/s²

7. A ball is thrown upward from the edge of a platform 15 m above the ground. The ball rises 12 m and then falls to the ground. What is the vertical displacement of the ball?

a. 15 m

*b. -15 m

c. -27 m

d. 27 m

8. The applied brakes of a car cause it to accelerate at a rate of -4m/s²for 6 s. How far does it take to stop if its initial velocity is 24 m/s?

a. 24 m

*b. 72 m

c. 28 m

d. 36 m

e. 144 m

9. A box, which is initially at rest, is moving with a constant acceleration of 1.20 m/s²over a distance of 32 m. What is the time required for the box to move this distance?

a. 5.16 s

b. 6.20 s

*c. 7.30 s

d. 26.0 s

10. A moving car slows to a stop. What is the direction of the acceleration of the car?

a. to the right of the car

b. north

c. down

*d. to the rear of the car

e. acceleration does not have direction

11. Accelerating means _____.

a. that there is a speed change

b. that there is a direction change

*c. either a change in the speed or direction (or both)

d. that the velocity is large

12. A 5 kg mass object is shot vertically with an initial speed of 47 m/s from ground level. How fast is the object traveling just before it hits the ground? Assume that there is no air resistance.

a. greater than 47 m/s

*b. equal to 47 m/s

c. less than 47 m/s

d. equal to 9.81 m/s

13. A car is moving with an initial speed of 30 m/s. The driver wishes to pass another car and accelerates at a rate of 0.7 m/s²for 6 seconds. How far does his car travel during this time and what is its final velocity? (round off)

*a. 193 m at a velocity of 34 m/s

b. 205 m at a velocity of 34 m/s

c. 193 m at a velocity of 26 m/s

d. 205 m at a velocity of 26 m/s

14. A car starts from rest and moves with constant acceleration of a m/s²for t s. Then it travels with constant speed for another t s before it slows to a stop with constant acceleration of -a m/s². How far does it travel?

*a. d = 2at²

b. d = 2at

c. d = at²

d. d = at

15. A vehicle is traveling at 15 m/s, when it starts accelerating at a constant acceleration of 3 m/s². How long must it accelerate before its average velocity, after it starts to accelerate, is equal to three times its initial velocity?

a. 15 s

*b. 20 s

c. 25 s

d. 30 s

16. An object that is dropped from the top of a building has a velocity of 30.7 m/s just before it hits the ground. How high is the building?

a. 96 m

*b. 48 m

c. 301 m

d. 602 m

17. A car accelerates at 4 m/s²for 5 seconds and then accelerates at 1 m/s²for another 5 seconds from initial velocity v₁to final velocity v_2.How does this affect the average velocity?

a. no change

*b. it will be greater then the average of v₁and v₂

c. It will be less than the average of v₁and v₂

e. none of the above

18. The horizontal position of a vehicle as a function of time is given by x = 2t²- 2t³. What is its average acceleration over the time interval from t = 0 to t = 2 s?

a. -4 m/s

b. 4 m/s

c. -6 m/s

d. 8 m/s

*e. -8 m/s