A loudspeaker at a rock concert generates $10^{- 2} W / m^{2}$ at $20 m$ at a frequency of $1 k H z$ . Assume that the speaker spreads its energy uniformly in all directions.What is the total acoustic power output of the speaker?

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Solution

Given:-
Intensity at 20 m = $10^{- 2} W / m^{2}$
Frequency = $1 K H z$
$(a) P = 4 π r^{2} I = 4 π \times 400 \times 10^{- 2} W = 50.3 W$ .

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A loudspeaker at a rock concert generates 10−2 W/m2 at 20 m at a frequency of 1 kHz. Assume that the speaker spreads its energy uniformly in all directions.What is the total acoustic power output of the speaker?

Given:- Intensity at 20 m = 10−2W/m2Frequency = 1KHz(a)P=4πr2I=4π×400×10−2W=50.3W.

A loudspeaker at a rock concert generates $10^{- 2} W / m^{2}$ at $20 m$ at a frequency of $1 k H z$ . Assume that the speaker spreads its energy uniformly in all directions.What is the total acoustic power output of the speaker?

Given:-
Intensity at 20 m = $10^{- 2} W / m^{2}$
Frequency = $1 K H z$
$(a) P = 4 π r^{2} I = 4 π \times 400 \times 10^{- 2} W = 50.3 W$ .