1.12 Analyzing Forces in Circular Motion

Select all correct statements.
Centripetal force:

• always points toward the center of a circular path

• is a net force (made of other forces)

• only exists on Earth

• is a fictitious force

• is always an equal & opposite reaction force to gravity

When a pendulum, hung from a ceiling, swings back and forth:

• there is no centripetal force

• there is centripetal force which is equal to the difference in tension and gravity forces

• there is a centripetal force which is equal to the sum of tension and gravity forces

• there is a centripetal force which is equal to the tension force

A tetherball (swinging around a post, attached to a rope) has centripetal force that is equal to

• the x component of gravity

• the y component of gravity

• the x component of tension

• the y component of tension

When the moon orbits the Earth, it experiences centripetal force caused by

• the Earth's gravity pulling on the moon

• the sun's gravity pulling on the Earth

• the tension force pulling on the moon

• the normal force pulling on the moon

What is the most general way to know that you're dealing with centripetal force?

• Your object is in the center.

• Your object is undergoing some sort of circular motion.

• There is gravity involved.

• There is tension involved.

Select all correct answers.

Centrifugal force:

• is a fictitious force

• acts in the same direction as centripetal force

• acts in the opposite direction as centripetal force

• only exists on Earth

• is always an equal and opposite reaction to air resistance

Select all correct answers.

Why are banked curves useful on a racetrack?

• Part of the normal force contributes to the centripetal force

• People can slide down from the audience

• You can turn faster without spinning out

• tension contributes to the centripetal force

True or false? As an object's period increases in circular motion, the centripetal force also increases.

• True

• False

True or false? Period and frequency are different ways of describing the same thing - how long it takes to complete 1 rotation/cycle.

• True

• False