A point source of sound is vibrating with a frequency of 256 vibrations per second in air and propagating energy uniformly in all directions at the rate of 5 joules per second. Calculate the amplitude of the wave at a distance of 25 m from the source. Assume non-dissipative medium [c=330m//s & density of air =1.29kg//m^(3)]

A point source of sound is vibrating with a frequency of 256 vibration

1.	A point source of sound is vibrating with a frequency of 256 vibrations per second in air and propagating energy uniformly in all directions at the rate of 5 joules per second. Calculate the amplitude of the wave at a distance of 25 m from the source. Assume non-dissipative medium [c=330m//s & density of air =1.29kg//m^(3)]
Answer» `0.8xx10^(-2)m` `0.8xx10^(-8)m` `10^(-6)m` `10^(-4)m` Solution :`l=2pi^(2)rhovA^(2)upsilon^(2)=(w)/(4pir^(2))` `thereforeA=[(W)/(8pi^(3)rhovupsilon^(2))]^(1//2).(1)/(R)cong10^(-6)m`

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