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Standard XII

Physics

Intuition of Wave Speed

A spherical s...

Question

A spherical source of power 4 W and frequency 800 Hz is emitting sound waves. The intensity of waves at a distance 200 m is

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Solution

The correct option is A

Intensity = $\frac{P o w e r}{A r e a} = \frac{4}{4 π \times (200)^{2}} = 7.9 \times 10^{- 6} W / m^{2}$

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A spherical source of power 4 W and frequency 800 Hz is emitting sound waves. The intensity of waves at a distance 200 m is

The correct option is A Intensity = PowerArea=44π×(200)2=7.9×10−6W/m2

The correct option is A

Intensity = $\frac{P o w e r}{A r e a} = \frac{4}{4 π \times (200)^{2}} = 7.9 \times 10^{- 6} W / m^{2}$