Circular motion

Earth and the Moon __ on an axis

• rotate
• revolve

The moon __ around Earth

• Rotates
• Revolves

A dog sits 1.5 m from the center of a merry-go-round. The merry-go-round is set in motion, and the dog’s tangential speed is 1.5 m/s. What is the magnitude of the dog’s centripetal acceleration?

• 3.9 m/s^2
• 2.8 m/s^2
• 1.5 m/s^2
• 11.5 m/s^2

A dog sits 1.50 m from the center of a merry-go-round and revolves at a tangential speed of 1.80 m/s. If the dog’s mass is 18.5 kg, what is the magnitude of the centripetal force on the dog?

• 56 N
• 21 N
• 40 N
• 98 N

A 10kg car travels at a constant speed of 20.0 m/s around a horizontal circular track. Which diagram correctly represent the direction of the car's velocity (v) and the direction of the centripetal force (Fc) acting on the car at a particular moment?

• 
• 
• 
• 

As the car goes around the curve, the centripetal force is directed--

• toward the center of the circular curve

• away from the center of the circular curve

• tangent to the curve in the direction of motion

• tangent to the curve opposite the direction of motion

The force that is necessary to keep the bucket swinging in a circle is called the:

• tangential velocity
• centrifugal force
• centripetal force
• the force of gravity

Which is true about centripetal force and centripetal acceleration?

• The centripetal acceleration is always pointing toward the center of an orbit and the centripetal force is always pointing outward

• The centripetal acceleration is always pointing outward from the center of an orbit and the centripetal force is always pointing inward

• The centripetal acceleration is always pointing toward the center of an orbit and the centripetal force also pointing toward the center but in a totally different location

• The centripetal acceleration is always pointing toward the center of an orbit and the centripetal force also pointing toward the center and in the same exact location as the centripetal acceleration

What happens to the centripetal force exerted on an object if you triple the velocity?

• it increases to 3X
• it decreases to 6X
• it increases to 6X
• it increases to 9X

Calculate the centripetal force required to make a 5 kg ball move 4 m/s in a circle with a radius of 2 m.

• 10 N
• 20 N
• 30 N
• 40  N