A2 · Topic 12

Motion in a circle.

Radians, angular speed, and the centripetal force that keeps a coin on a turntable, a ball on a string and a planet in orbit. Play the simulations, then test yourself on original Paper 4 style questions.

Simulations · live
Interactive · live The centripetal tracker Angular speed, linear speed, acceleration and the centre-pointing force. Loads only when you launch, so the page stays fast.
Interactive · live Tension around the loop Why the string tension peaks at the bottom of a vertical circle. Loads only when you launch, so the page stays fast.
Interactive · live The conical pendulum Spin it faster and watch the cone open as the angle grows. Loads only when you launch, so the page stays fast.
Paper 4 practice · live
Structured questions · with worked solutions Ten original Paper 4 style questions A full topic set covering angular quantities and centripetal force, each question linked to its lesson, with worked solutions. Open practice →
Lessons · live
Angular quantities Centripetal acceleration and force
Concept map
Open the concept map