Power of a Source: Calculating Intensity & Power

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The discussion revolves around calculating the power radiated by a loudspeaker based on its intensity and area. The speaker has a circular opening with a diameter of 20 cm, leading to an area calculation of approximately 0.0314 m². Using the formula for intensity (power/area), the power is calculated to be 6.28 x 10^(-6) watts. The original poster expresses confidence in their solution, questioning if the problem was too simple. The calculations and reasoning presented appear to be correct.
Amith2006
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Sir,
A loud speaker having a circular opening of diameter 20 cm is emitting sound waves uniformly. The intensity of sound at the opening is 0.2 milli watt/m^2. What is the power radiated by the source?
I solved it in the following way:
Intensity = power/Area
Here Area = (pi)R^2
= 3.14 x 0.01
= 0.0314 m^2
Power = 0.2 x 0.0314 milli watts
= 6.28 x 10^(-6) watts
Is it right?
 
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Looks correct to me. Did you think it was too easy?
 
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