- Intensity is the power transferred per unit area, where the area is an imagined surface that is perpendicular to the direction of propagation of the energy The energy of a wave depends on its amplitude and frequency.
- Considering a mechanical wave,
a particle on a wave oscillates with simple harmonic motion,
its maximum velocity is given by
- The intensity of a wave is defined as the amount of energy that passes
though unit area perpendicular to the wave direction in unit time.
- If the amplitude is doubled the maximum velocity is doubled.
- The kinetic energy = ×mass×velocity2
- Thus on doubling the velocity you quadruple the kinetic energy,
that further quadrupling the intensity of the wave.