# IB DP Physics: HL复习笔记9.1.2 Energy Changes in SHM

### Energy Changes in SHM

• During simple harmonic motion, energy is constantly exchanged between two forms:
• Kinetic energy
• Potential energy
• The potential energy could be in the form of:
• Gravitational potential energy (for a pendulum)
• Elastic potential energy (for a horizontal mass on a spring)
• Or both (for a vertical mass on a spring)
• The speed of an oscillator is at a maximum when displacement x = 0, so:

The kinetic energy of an oscillator is at a maximum when the displacement is zero

• Therefore, the kinetic energy is zero at maximum displacement x = x0, so:

The potential energy of an oscillator is at a maximum when the displacement (both positive and negative) is at a maximum,