PS Unit 2 S2 Review

Which arrow represents the normal force on the box?

• B

• D

• A

• C

Which of the forces represents the tension force on the box?

• C

• B

• A

• D

A 5 kg bowling ball is moving 0.2 m/s to the left. How much gravitational force is acting on the ball?

• 1 N

• 49 N

• 0.2 N

• 9.8 N

In which direction is the overall force acting on the ball?

• upwards

• downwards

• to the left

• to the right

What effect does the increase in speed have on the frictional force between the bike and sidewalk?

• The frictional force doubles because when speed increases frictional force also increases.

• The frictional force increases, but does not double because although friction increases with increasing speed, it does not increase as fast.

• The frictional force becomes half of what it was because when speed increases, frictional force decreases.

• The frictional force between the bike and sidewalk stays the same because speed does not affect frictional force.

A ball moves along a smooth metal surface while an identical ball moves along concrete. Which surface exerts a smaller amount of frictional force on the ball?

• The concrete surface exerts less frictional force on the ball because there are fewer bumps and irregularities on the concrete than there are on the metal.

• The concrete and metal surfaces exert the same amount of frictional force on the ball because they are both solid surfaces.

• Neither concrete nor metal exert any friction on the ball because these two surfaces never result in a frictional force on any object.

• The metal surface exerts less frictional force because there are fewer bumps and irregularities on it than there are on the concrete.

Which of the following choices describes how static equilibrium could have been achieved when the object was pushed?

• A backward force of 10 N was exerted on the box at exactly five seconds so that the forces were balanced, and the object remained at rest.

• A force greater than 10 N was exerted in a forward direction on the object at exactly five seconds so that the forces were balanced, and the object remained at rest.

• A force greater than 10 N was exerted straight down on the object, countering the normal force.

• A force of exactly 10 N was exerted straight down on the object, countering the normal force.

A large box remains at rest on a sidewalk while a person pushes it with a force to the right. Which of the following choices shows the correct force diagram for this situation?

• Diagram with friction opposing applied force, normal and gravitational forces balanced.

• Diagram with applied force greater than friction, causing movement.

• Diagram with no friction force shown.

• Diagram with gravitational force greater than normal force.

Which force acts upwards on the box in the diagram?

• Normal force

• Frictional force

• Applied force

• Gravitational force

What is the direction of the gravitational force acting on the box in the diagram?

• Upwards

• Downwards

• To the left

• To the right