physical science test prep review

A baseball bat hits a baseball with a force of 100 Newtons. What is the force and its direction exerted by the ball on the bat?

• 100 Newtons, same direction

• 100 Newtons, opposite direction

• 200 Newtons, same direction

• 200 Newtons, opposite direction

The head of a hammer is often made of steel. This makes the head heavy, which helps create a strong force for driving nails. Steel is also strong. The head of a hammer must be strong to resist what force?

• The force of the air resistance on the moving hammer

• The force of the person using the hammer

• The force of gravity pulling down on the hammer

• The force of the nail pushing in the opposite direction

According to Newton’s Third Law, if someone jumps off a skateboard, the skateboard will roll backwards because:

• the mass of the skateboard is the same as the mass of the person jumping off.

• the pull of gravity on the person is the same as on the skateboard, regardless of size.

• the air resistance on the person is great and the friction on the skateboard is small.

• for the force that sent the person forward, there is an equal force pushing back on the skateboard.

If a moving object changes direction, there must be a change in:

• mass.

• frame of reference.

• force.

• friction.

The illustration shows the forces in Newtons (N) acting on three different blocks. Which blocks will experience a change in motion, or acceleration?

• Blocks 1 and 2

• Blocks 2 and 3

• Blocks 1 and 3

• Blocks 1, 2, and 3

The illustration shows all the forces in Newtons (N) acting on a box. The sum of all the forces acting on the box results in a force acting on the box:

• to the right with a strength of 11 Newtons

• to the left with a strength of 7 Newtons

• to the right with a strength of 25 Newtons

• to the left with a strength of 6 Newtons

The data on the table provide evidence for which of the following conclusions?

• The force between any two magnets is always constant, regardless of distance.

• As distance between electromagnets increases, the electromagnetic force also increases.

• The smaller the distance between two electromagnets, the greater the force.

• The force between two magnets depends only on the charge of the electromagnets.

Students want to investigate how the amount of electric energy delivered to a motor affects its speed. Which of the following procedures will most likely produce the data students need to answer their question?

• Measure the rotations per second of a motor when it is connected to one battery, two batteries, and three batteries.

• Add larger and larger motors to a battery to determine the size of the largest motor the battery is able to run.

• Closely observe the rotation of the motor to see if the direction of spin reverses when the poles of the battery are switched.

• Connect a series of motors to the same battery to figure out how many motors can be run off the same battery.

If Saturn’s mass was reduced, the distance between Saturn and the Sun would have to—

• increase to keep the same gravitational attraction.

• stay the same so that the gravitational force would stay the same.

• decrease to keep the same gravitational attraction.

• double to keep the same gravitational attraction.

The gravitational force between two objects will be very small, unless which of the following is true?

• The objects must be very far apart.

• One of the objects must have a very large mass.

• Both objects must have very large masses.

• Both objects must be in the solid state of matter.