Forces and Energy in Motion

Which of the following best describes Newton's Third Law of Motion?

• An object at rest stays at rest unless acted upon by an external force.

• For every action, there is an equal and opposite reaction.

• The acceleration of an object is directly proportional to the net force acting on it.

• The force of gravity acts between all masses.

If two ice skaters push off each other, what will happen according to Newton's Third Law?

• Both skaters will move in the same direction.

• Both skaters will move in opposite directions.

• Only one skater will move.

• Neither skater will move.

What is the formula for calculating the force acting on an object?

Which of the following factors does NOT affect the kinetic energy of an object?

• Mass of the object

• Speed of the object

• Height of the object

• Direction of the object's motion

If the mass of an object is doubled, what happens to its kinetic energy, assuming speed remains constant?

• It remains the same.

• It doubles.

• It triples.

• It quadruples.

Which graph correctly represents the relationship between kinetic energy and speed?

• A linear graph

• A parabolic graph

• A constant graph

• An exponential graph

What is the unit of force in the International System of Units (SI)?

• Joule

• Newton

• Watt

• Pascal

If a car accelerates from rest to a speed of 20 m/s, what happens to its kinetic energy?

• It decreases.

• It remains the same.

• It increases.

• It becomes zero.

Which of the following is an example of Newton's Third Law in action?

• A book resting on a table

• A rocket launching into space

• A car moving at constant speed

• A pendulum swinging

What happens to the motion of an object if the net force acting on it is zero?

• It accelerates.

• It decelerates.

• It moves at a constant speed.

• It changes direction.