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Question
Answer briefly.
State the expression for apparent frequency when the source is stationary and the listener is
- moving towards the source
- moving away from the source
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Solution
- Let, n = actual frequency of the source.
n0 = apparent frequency of the source.
v = velocity of sound in air.
vs = velocity of the source.
vL = velocity of the listener. - If listener is moving towards source then apparent frequency is given by,
n = `"n"_0(("v + v"_"L")/"v")`, i.e., apparent frequency increases. - If listener is receding away from source then apparent frequency is given by,
n = `"n"_0(("v - v"_"L")/"v")`, i.e., apparent frequency decreases.
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