Menu

Energy in SHM

Part of the Mechanics section of Coddy's Physics journey. Lesson 82 of 94.

The total energy stays constant, shared between the spring and the block:

½kx² + ½mv² = ½kA²

Energy of an oscillator against its position x from minus A to A: the elastic energy is a U-shaped curve, zero at 0 and largest at the ends; the kinetic energy is an upside-down U, largest at 0 and zero at the ends; their sum is a flat line, the total energy

Elastic plus kinetic energy is the same at every position.

At x = ±A: all elastic, the block stops. At x = 0: all kinetic, the speed is largest.

challenge icon

Challenge

A 0.2 kg block oscillates on a spring with k = 80 N/m and a total energy of 2.5 J. Find its speed v as it passes x = 0.15 m.

Try it yourself

quiz iconTest yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Mechanics