Question

quiz
question 7 of 10

newton’s first law of motion states that an object in motion tends to stay in motion unless it

choose one option

a starts to decelerate.

b runs out of kinetic energy.

c is acted upon by another force.

d approaches the speed of light.

Explanation:

Newton's First Law of Motion (Law of Inertia) states that an object at rest stays at rest, and an object in motion stays in motion with the same velocity (constant speed and direction) unless a net external force acts on it.

• Option A: Deceleration is a result of a force (like friction), not a cause for changing motion on its own.
• Option B: Kinetic energy change is due to work done by forces; running out of kinetic energy isn’t the reason motion changes (forces cause energy changes).
• Option C: Matches the law—external force is required to change an object’s state of motion.
• Option D: Newton’s laws apply to non - relativistic speeds; the speed of light is a relativistic concept, not related to Newton’s first law.

Answer:

C. is acted upon by another force.