As a wave propagates - Vidyadip

MCQ

As a wave propagates

A
The wave intensity remains constant for a plane wave
B
Total intensity of the spherical wave over the spherical surface centered at the source remains constant at all times
C
The wave intensity decreases as the inverse square of the distance from the source for a spherical wave
✓
All of the above.

✓

Answer

Correct option: D.

All of the above.

d
(d) For a travelling wave, the intensity of wave remainsconstant if it is a plane wave.
Intensity of wave is inversely proportional to the square of the distance from the source if the wave is spherical
$\left( {I = \frac{P}{{4\pi {r^2}}}} \right)$
Intensity of spherical wave on the spherical surface centred at source always remains same. Here total intensity means power $P$.

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