Practice Circular Motion in Physics

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

Motion of an object along a circular path where the speed may be constant but the velocity is continuously changing direction, requiring a centripetal acceleration.

A car on a circular track at constant speed is still accelerating—toward the center.

Showing a random 20 of 50 problems.

Example 1

medium
A car drives at 20 m/s around a curve. To halve its centripetal acceleration, by what factor should the radius change?

Example 2

easy
An object speeds around a circle of radius 5 m at 10 m/s. Centripetal acceleration?

Example 3

medium
A point at radius r and one at radius 2r on the same rigid wheel. Compare their speeds.

Example 4

challenge
A roller-coaster loop of radius 8 m. What minimum speed at the top guarantees riders stay seated (use g=9.8)?

Example 5

medium
A point moves in a circle of radius 4 m, completing a revolution in 8 s. Find its speed.

Example 6

easy
An object completes a circle of radius 3 m. What distance does one revolution cover?

Example 7

medium
A point on the rim of a bicycle wheel (r=0.35 m) moves at 5 m/s. What is the period of rotation and the centripetal acceleration?

Example 8

medium
A wheel turns through one revolution in 0.5 s, radius 0.4 m. Find the tip speed.

Example 9

medium
An object needs centripetal acceleration 18 m/s2 on a radius 2 m. Find its speed.

Example 10

challenge
A coin sits 0.1 m from the center of a turntable. If max static friction gives a=2 m/s2, find the maximum frequency before it slips.

Example 11

easy
At constant speed on a circle, is the velocity changing?

Example 12

easy
An object moves at constant v=8 m/s on a circle of radius r=4 m. Find the centripetal acceleration.

Example 13

easy
Period T=4 s for one revolution. What is the frequency?

Example 14

easy
A wheel spins so a point goes around in 2 s. How many revolutions in 10 s?

Example 15

hard
A ball on a 0.8 m string is swung in a vertical circle. What minimum speed must it have at the top of the circle so the string remains taut? Use g=9.8 m/s2.

Example 16

medium
A car on a curve of radius 40 m has ac=4 m/s2. Find its speed.

Example 17

challenge
Earth orbits the Sun at radius 1.5×1011 m with period T=3.16×107 s. Find the centripetal acceleration.

Example 18

easy
A car rounds a circular track at constant speed. Is it accelerating?

Example 19

medium
A satellite orbits at constant v=7000 m/s at radius 7×106 m. Find the centripetal acceleration.

Example 20

medium
A satellite orbits Earth at a radius of 6.8×106 m with a period of 5400 s. What is its orbital speed and centripetal acceleration?