Physics Test: Forces and Motion in 1-D
Put all answers and scrap work on the answer sheet. Do not write on this exam. Assume there is no air resistance unless stated.
1. In the graph shown, what is the average velocity from 0 to 4.0 s?
a. 0
b. 10 m/s
c. 20 m/s
d. -40 m/s
2. In the graph above the displacement from 0 – 6 seconds is:
a. 80 m
b. 40 m
c. 6 m
d. 0 m
3. A ball is thrown straight up, reaches a maximum height, then falls to its initial height. As the ball is going up,
a. both its velocity and its acceleration point upward.
b. its velocity points upward and its acceleration points downward.
c. its velocity points downward and its acceleration points upward.
d. both its velocity and its acceleration points downward.
4. If the displacement versus time graph of an object is a horizontal line, the object is
a. moving with constant non-zero speed.
b. moving with constant non-zero acceleration.
c. at rest.
d. moving with infinite speed.
5. Acceleration is represented in a position vs time graph by:
a. a horizontal line
b. a straight line that passes through the x-axis
c. a straight line that is angled up
d. any change is slope
6. A cart with an initial velocity of 5.0 m/s experiences a constant acceleration of 2.0 m/s2. What is the cart's displacement during the first 6.0 s of its motion?
a. 10 m
b. 55 m
c. 66 m
d. 80 m
7. A ball is tossed up at an initial velocity of 25 m/s at the edge of a cliff. What is its displacement from its starting position after the ball reaches a final velocity of 35 m/s down?
a. 61.0 m
b. 30.5 m
c. -61.0 m
d. -30.5 m
8. Can an object have positive velocity while having negative acceleration?
a. No, because when moving forward you must have a positive acceleration.
b. No, because if acceleration is negative, then the objects velocity must also be negative.
c. Yes, and an example would be a car speeding up from 0 to 20 m/s.
d. Yes, and an example would be a car slowing down from 20 to 0 m/s.
9. A ball, after an initial kick, moves straight up in the air. The motion of the ball is best described as:
a. travels at constant velocity up.
b. has a constant acceleration directed up when moving up, but a different constant acceleration directed down when moving down.
c. has a constant acceleration directed up when moving up, and has the same value of constant acceleration directed down when falling down.
d. has the same constant acceleration directed down for moving up and moving down.
10. A bullet shot straight up returns to its starting point in 10 s. What is the initial speed of the bullet?
a. 9.8 m/s
b. 25 m/s
c. 49 m/s
d. 98 m/s
11. Ball A is dropped from the top of a tall building. One second later, ball B is dropped from the same building. As time progresses, the distance between the balls… (don’t forget to think.)
a. increases.
b. remains constant.
c. decreases.
d. cannot be determined from the information given.
12. If the position versus time graph of an object is a curved line of decreasing slope, the object is:
a. moving with constant velocity
b. speeding up
c. slowing down
d. at rest
13. A ball is thrown straight up. When the ball reaches the highest point
a. both its velocity and its acceleration are zero.
b. its velocity is zero and its acceleration is not zero.
c. its velocity is not zero and its acceleration is zero.
d. neither its velocity nor its acceleration is zero.
14. A car travels at 15 m/s for 10 s. It then speeds up with a constant acceleration of 2.0 m/s2 for 15 s. At the end of this time, what was the total distanced traveled by the car?
a. 150 m
b. 300 m
c. 450 m
d. 600 m
15. Two objects are thrown from the top of a tall building. One is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hit the street? (think…..)
a. The one thrown up is traveling faster.
b. The one thrown down is traveling faster.
c. They are traveling at the same speed.
d. It is impossible to tell because the height of the building is not given.
16. Which type of motion is covered in Newton’s 1st law of motion?
a. Circular motion at a constant speed
b. Slowing down in straight line
c. Speeding up in a straight line
d. Constant velocity
17. A net force F accelerates a 10 kg mass with an acceleration 4 m/s2. If the same net force is applied to 20 kg mass, then the acceleration will be
a. 1 m/s2
b. 2 m/s2
c. 4 m/s2
d. 8 m/s2
18. A 20-ton truck collides with a 1500-lb car and causes a lot of damage to the car. Since a lot of damage is done on the car
a. the force on the truck is greater then the force on the car.
b. the force on the truck is equal to the force on the car.
c. the force on the truck is smaller than the force on the car.
d. the truck did not slow down during the collision.
19. The total number of forces, in both the x and y directions, acting on a box being pushed across a rugged floor is:
a. one.
b. two.
c. three.
d. four.
20. What is the acceleration due to gravity on a planet where a 20 kg box weighs 100 N?
a. 5 m/s2
b. 10 m/s2
c. 15 m/s2
d. 20 m/s2
21. A 20 kg mass and a 5.0 kg mass are dropped simultaneously from the same height. Ignore air resistance. What happens, and why?
a. The 20 kg mass accelerates faster because it is heavier.
b. The 5 kg mass accelerates faster because it has less inertia.
c. They both accelerate at the same rate because they have the same force to mass ratio.
22. In the absence of all forces, a moving object will
a. slow down and eventually stop.
b. move at constant velocity forever.
c. immediately come to rest.
d. Cannot determine without more detail.
23. Mass is a measure of:
a. weight
b. inertia
c. force
d. acceleration
24. Weight is a measure of:
a. the force of gravity
b. pressure
c. inertia
d. mass
25. Inertia represents an object’s tendency to:
a. willingly change in motion
b. remain at rest
c. remain in motion
d. resist a change in motion
26. Starting from rest, a 4.0 kg body reaches a speed of 8.0 m/s in 2.0 s. What is the net force acting on the body?
a. 4.0 N
b. 8.0 N
c. 16 N
d. 32 N
27. What is the normal force on a 10 kg block being dragged to the right by a rope with a tension of 150 across a level rugged floor with a friction of 75 N at an acceleration of 5 m/s2?
a. 50.0 N
b. 98.1 N
c. 148.1 N
d. 250.0 N
28. String 1 is pulled on with a force of 50 N to the right. String 1 is attached to a mass of 20 kg on a level surface. String 2 connects the 20 kg mass to a second mass of 40 kg. Friction can be ignored. Find the tension force in string 2.
a. 11.3 N
b. 33.3 N
c. 50 N
d. 83.3 N
29. A 4 kg mass hangs by a string that passes over a pulley and connects to a 12 kg mass. The system is let go and the 12 kg mass descends. What is the acceleration of the system?
a. 2.4 m/s2
b. 4.9 m/s2
c. 7.4 m/s2
d. 9.8 m/s2
30. A box on a table has a mass of 4 kg. There is a string connecting the box, going over a pulley to a hanging mass of 8 kg. The box on the table experiences of friction force of 20 N as it is dragged across the table. Find the tension in string as the system accelerates:
a. 12.8 N
b. 25 N
c. 39.2 N
d. 78.5 N
31. A person with a mass of 80 kg stands on a bathroom scale in an elevator that is accelerating up at a rate of 2 m/s2. What weight does the scale read?
a. 625 N c. 945 N
b. 785 N d. 0 N