A wave travels on a light string. The equation of the wave is Y = A sin(kx - ωt + 30°). It is reflected from a heavy string tied to an end of the light string at x = 0. If 64% of the incident energy is reflected the equation of the reflected wave is
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Question

A wave travels on a light string. The equation of the wave is Y = A sin(kx - ωt + 30°). It is reflected from a heavy string tied to an end of the light string at x = 0. If 64% of the incident energy is reflected the equation of the reflected wave is

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G1 Physics · Accepted Answer

Step 1: Reflected energy fraction 0.64 gives reflected amplitude ratio √0.64 = 0.8. Step 2: Reflection from the heavier string introduces a phase reversal of π and reverses the propagation direction. Step 3: The reflected wave is 0.8A sin(kx+ωt−30°), equivalent to the keyed form. Final: C.

A wave travels on a light string. The equation of the wave is Y = A sin(kx − ωt + 30°). It is reflected from a heavy string tied to an end of the light string at x = 0. If 64% of the incident energy is reflected the equation of the reflected wave is