1. an object is moving to the right in a straight line. the net force acting on the object is also directed to the right, but the magnitude of the force is decreasing with time. how will the motion of the object change?
a. it will continue to move to the right, its speed increasing with time.
b. it will stop and then begin moving to the left.
c. it will continue to move to the right at a constant speed.
d. it will continue to move to the right, its speed decreasing with time.
2. a glass table top is able to exert a maximum normal force of 1600 n. a large object with a mass of 165 kg is gently lowered onto the center of the table top, then released there. what most likely will happen next?
a. the table top will crack but still hold the object.
b. the table top will break and the object will fall to the floor.
c. the object will bounce off the table.
d. the object will rest on the table top, which remains in tact.
3. a rock at rest has weight 138 n. what is the weight of the rock when it is accelerating upward at 12 m/s2?
a. 115 n
b. 63 n
c. 304 n
d. 138 n
4. a chair of mass 30.0 kg is at rest on a horizontal floor. the floor is not frictionless. you push on the chair with a force of 80.0 n directed at an angle of 35.0° to the floor. what is the normal force that the floor exerts on the chair?
a. 363 n
b. 340 n
c. 294 n
d. 317 n
5. two particles are separated by a distance d. at this distance, the strong interaction between them is much greater than the electrical interaction. what are the possible values of d?
a. extremely large values, such as the distances between the planets and sun
b. extremely small values, such as the distances between particles in an atomic nucleus
c. values between 1 mm and 1 m
d. values between 1 m and 1 km
6. a soccer player kicks a ball. why does the action force exerted by the player's foot cause a different motion than the reaction force?
a. the action force and the reaction force act on different objects.
b. the action force is greater than the reaction force.
c. the reaction force is greater than the action force.
d. the action force and the reaction force act in opposite directions.
7.
a box of weight 320 n is being pulled to the right by a pulling force f-> of magnitude 44 n. the coefficient of static friction between the box and the floor is 0.15. to make an accurate free-body diagram of the box, the letter f in the diagram above should be replaced with the label
a. 4.0 n
b. 48 n
c. 44 n
d. 280 n
8. i have the answer
9. a man pulls a wagon with a handle that is at an angle of 42° with the ground. if the man pulls with 330 n of force, how much force pulls the wagon forward?
a. 110 n
b. 220 n
c. 245 n
d. 330 n
10.
in this free-body diagram, the weight (w) and normal force (n) have equal magnitudes. the magnitudes of any forward or backward forces, however, are not determined. the free-body diagram will not apply to which of these objects or persons?
a. a box sliding across a table at constant speed
b. an automobile accelerating on a flat highway
c. a box at rest on a table
d. a woman jumping off the floor
11. a force of 1 n will cause a mass of 1 kg to have an acceleration of 1 m/s2. therefore, a force of 8 n applied to a mass of 1 kg will cause it to accelerate at what rate?
a. 8 m/s2
b. 0.13 m/s2
c. 1 m/s2
d. 9 m/s2
e. 64 m/s2