Present below are functions of x and t to describe the displacement (longitudinal or transverse) of an elastic wave. Identify the ones describing

(a) a stationary wave,

(b) a travelling wave and

(c) neither of the two :

(i) y = 3 sin( 5x – 0.5t ) + 4cos( 5x – 0.5t )

(ii) y = cosxsint + cos2xsin2t.

(iii) y = 2 cos (3x) sin (10t)

(iv) y = $$2\sqrt{x – vt}$$

Asked by Pragya Singh | 1 year ago |  138

##### Solution :-

(i) This equation describes a travelling wave as the harmonic terms ωt and kx are in the combination of kx – ωt.

(ii) This equation describes a stationary wave because the harmonic terms ωt and kx appear separately in the equation. In fact, this equation describes the superposition of two stationary waves.

(iii) This equation describes a stationary wave because the harmonic terms ωt and kx appear separately.

(iv) This equation does not contain any harmonic term. Thus, it is neither a travelling wave nor a stationary wave.

Answered by Abhisek | 1 year ago

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