Question

Which statements about inertia and centripetal force are correct? Check all that apply.

Inertia is always present.
Inertia causes objects to continue moving in circles.
Centripetal force is always present.
Centripetal force pulls objects toward the center of a circle.
Inertia and centripetal force cause circular motion.

Answer 1

Correct:
- Inertia is always present. (Any object with mass has inertia — a tendency to resist changes in its motion.)
- Centripetal force pulls objects toward the center of a circle. (“Centripetal” means a net force directed radially inward.)

Incorrect:
- Inertia causes objects to continue moving in circles. (False — inertia makes objects keep moving in a straight line at constant speed unless acted on by a force.)
- Centripetal force is always present. (False — a centripetal force exists only when an object is undergoing circular (or curved) motion; it is the net inward force required for that motion.)
- Inertia and centripetal force cause circular motion. (Misleading/false — circular motion is caused by a centripetal force. Inertia does not cause the turn; it resists it and determines how large the centripetal force must be: Fc = m v^2 / r.)