Physics Quiz

How is the motion of an object affected when a force acts on it?

• It stops a moving object.

• It isn't; forces don't affect the motion of an object.

• It moves in the direction that the force is being applied.

• It accelerates.

Multiple Choice: How does air resistance affect the acceleration of a falling object?

• It acts in the same direction of gravity, increasing acceleration.

• It acts in the opposite direction of gravity, increasing acceleration.

• It acts in the same direction of gravity, reducing acceleration.

• It acts in the opposite direction of gravity, reducing acceleration.

Suppose that Charlie and David are pulling on a car in opposite directions. Charlie pulls on the car with 400 N of force, and David pulls on the car with 450 N of force. What's the net force on the car, ignoring static friction?

• 950 N towards David

• 50 N towards Charlie

• 950 N towards Charlie

• 50 N towards David

Two identical coins are knocked off a table at the same time by different forces. Which coin will hit the floor first?

• The coin with the heavier force applied

• The coin with the lighter force applied

• The heavier coin

• Both will hit the floor at the same time

Why do projectiles follow a curved path?

• An initial forward velocity

• Downward vertical force of gravity

• An initial vertical velocity

• Forwards force of gravity

• Upward vertical force of gravity

Inertia is...

• an object's tendency to resist changes in motion.

   

• an object's mass.

• an object's tendency to resist moving.

• an object's tendency to keep moving.

To calculate mass in kg, we need to 

• divide force in N by acceleration in m/s^2.

• multiply force in N by acceleration in m/s^2.

• divide force in N by acceleration in m/s.

• divide acceleration in m/s^2 by force in N.

Mass is

• measured in Newtons.

• a measure of the force of gravity acting on an object.

• a measure of the inertia of an object.

• the amount of matter in an object.

During a test crash, an air bag inflates to stop a dummy's forward motion. The dummy's mass is 75 kg. If the net force on the dummy is 825 N toward the rear of the car, the dummy's rate of deceleration is ________ m/s^2.

A bicycle takes 8.0 seconds to accelerate at a constant rate from rest to a speed of 4.0 m/s. If the mass of the bicycle and rider together is 85 kg, the net force acting on the bicycle and rider is __________ N.