Force concept inventory

• about half as long for the heavier ball as for the lighter one.

• about half as long for the lighter ball as for the heavier one.

• about the same for both balls.

• considerably less for the heavier ball, but not necessarily half as long.

• considerably less for the lighter ball, but not necessarily half as long.

The two metal balls of different weights roll off a horizontal table with the same speed.

In this situation:

• both balls hit the floor at approximately the same horizontal distance from the base of the

  table.

• the heavier ball hits the floor at about half the horizontal distance from the base of the

  table than does the lighter ball

• the lighter ball hits the floor at about half the horizontal distance from the base of the

  table than does the heavier ball

• the heavier ball hits the floor considerably closer to the base of the table than the lighter

  ball, but not necessarily at half the horizontal distance

• the lighter ball hits the floor considerably closer to the base of the table than the heavier

  ball, but not necessarily at half the horizontal distance

A stone dropped from the roof of a single story building to the surface of the earth:

• reaches a maximum speed quite soon after release and then falls at a constant speed

  thereafter.

• speeds up as it falls because the gravitational attraction gets considerably stronger as the

  stone gets closer to the earth

• speeds up because of an almost constant force of gravity acting upon it.

• falls because of the natural tendency of all objects to rest on the surface of the earth.

• falls because of the combined effects of the force of gravity pushing it downward and the

  force of the air pushing it downward.

A large truck collides head-on with a small compact car. During the collision:

• the truck exerts a greater amount of force on the car than the car exerts on the truck.

• the car exerts a greater amount of force on the truck than the truck exerts on the car.

• neither exerts a force on the other, the car gets smashed simply because it gets in the way

  of the truck.

• the truck exerts a force on the car but the car does not exert a force on the truck.

• the truck exerts the same amount of force on the car as the car exerts on the truck.

Consider the following distinct forces:

1. A downward force of gravity.

2. A force exerted by the channel pointing from q to O.

3. A force in the direction of motion.

4. A force pointing from O to q.

• 1 only

• 1 and 2.

• 1 and 3

• 1, 2, and 3.

• 1, 3, and 4

Which path in the figure would

the ball most closely follow after it

exits the channel at "r" and moves

across the frictionless table top?

• A

• B

• C

• D

• E

A steel ball is attached to a string and is

swung in a circular path in a horizontal

plane as illustrated in the accompanying

figure.

At the point P indicated in the figure, the

string suddenly breaks near the ball.

If these events are observed from directly

above as in the figure, which path would

the ball most closely follow after the

string breaks?

• A

• B

• C

• D

• E

A ball is fired by a cannon from the top of a cliff as shown in the figure below. Which of

the paths would the cannon ball most closely follow?

• A

• B

• C

• D

• E

A boy throws a steel ball straight up. Consider the motion of the ball only after it has left the

boy's hand but before it touches the ground, and assume that forces exerted by the air are

negligible. For these conditions, the force(s) acting on the ball is (are):

• a downward force of gravity along with a steadily decreasing upward force.

• a steadily decreasing upward force from the moment it leaves the boy’s hand until it

  reaches its highest point; on the way down there is a steadily increasing downward

  force of gravity as the object gets closer to the earth.

• an almost constant downward force of gravity along with an upward force that steadily

  decreases until the ball reaches its highest point; on the way down there is only a

  constant downward force of gravity.

• an almost constant downward force of gravity only

• none of the above. The ball falls back to ground because of its natural tendency to rest

  on the surface of the earth.

An elevator is being lifted up an elevator shaft at a constant speed by a steel cable as shown

in the figure below. All frictional effects are negligible. In this situation, forces on the

elevator are such that:

• the upward force by the cable is greater than the downward force of gravity.

• the upward force by the cable is equal to the downward force of gravity.

• the upward force by the cable is smaller than the downward force of gravity.

• the upward force by the cable is greater than the sum of the downward force of gravity

  and a downward force due to the air.

• none of the above. (The elevator goes up because the cable is being shortened, not

  because an upward force is exerted on the elevator by the cable).