Please Prove the fact that intensity is directly proportional to amplitude of the wave...

Asked by nitishkrnehu09 | 9th Oct, 2017, 06:56: PM

Expert Answer:

- 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 
 
v=2π×frequency×amplitude
 
- 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 = 1 half×mass×velocity2
- Thus on doubling the velocity you quadruple the kinetic energy,
that further quadrupling the intensity of the wave.

Answered by Abhijeet Mishra | 10th Oct, 2017, 06:23: PM