The displacement of particle in wave equation is represented as

y = 1.2 sin (120 πt - 0.20x)

If this is made to incident on the rigid wall and its amplitude falls to 40% reflection from wall, then what is the equation of reflected wave?

### Asked by Topperlearning User | 22nd May, 2015, 03:32: PM

It is given amplitude of reflected wave falls to 40% Therefor amplitude of reflected wave

A_{ref} = = 0.48

We know that on reflection the direction of propagation of wave reverses and on reflection from rigid wall, the phase changes by π.

Therefor equation of reflected wave is

y = 0.48 sin [120 πt - 0.20(-x) + π]

= 0.48 sin [120 πt + 0.20x + π]

= 0.48 sin (120 πt + 0.20x)

### Answered by | 22nd May, 2015, 05:32: PM

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