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Blazing goIITian

Joined:	24 Dec 2007
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6 Jan 2009 14:20:37 IST

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Find Ratio Of Pressure Amplitudes

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2 sound waves in the same direction have average power transmitted in the ratio 1:1

Also ration of their wavelengths lambda1/lambda2 = 1:2

Find ratio of their pressure amplitudes

0.5

Comments (4)

Prakhar Banga

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6 Jan 2009 15:32:24 IST

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average power transmitted is proportional to A^2 f^2
P1/P2 = A1^2 f1^1 / (A2^2 f2^2)
1 = (A1^2/A2^2) (lambda2^2 / lambda1^2)
So (A1^2/A2^2) = 1/4 or A1/A2 = 0.5
Option d).

Madmax

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6 Jan 2009 15:57:23 IST

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wht is the formula for average power transmitted??

Prakhar Banga

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6 Jan 2009 16:03:13 IST

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The average power transmitted is proportional to A^2 f^2. It is 2 pi^2 A^2 f^2 (rho) S v, where rho is density of medium, S is cross sectional area of the volume in which wave is present and v its velocity.

Sagar Saxena

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7 Jan 2009 01:45:21 IST

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hello dear

the formula for energy per unit area per second is 1/2 (rho) c (omega)² A²

pressure is directly proportional to (rho) c (omega)² A²

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