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Question
State the expression for apparent frequency when listener is stationary and source is moving towards the listener.
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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.
v1 = velocity of the listener.
If source is moving towards observer then apparent frequency is given by,
n = `"n"_0("v"/("v" - "v"_"s"))`, i.e., apparent frequency increases.
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