The intensity of the waves from a point source at a distance d from the source is I. What is the intensity at a distance 2d from the source?
A)4I
B)2I
C)I/2
D)I/4
E)I/ $\sqrt { 2 }$

Question

Quizplus · Accepted Answer

The intensity of waves from a point source follows the inverse square law, meaning it is inversely proportional to the square of the distance from the source. Therefore, if the distance is doubled (from d to 2d), the intensity becomes one-fourth (I/4) of the original intensity.

The Intensity of the Waves from a Point Source at a Distance