The intensity I of a wave is related to the distance the wave travels by the expression I ? 18 1/r². The assumptions on which this formula depend include all of the following except A) the wave energy travels outward into three-dimensional space. B) the medium is homogeneous. C) the medium is nonabsorptive. D) none of the above.

Question

Quizplus · Accepted Answer

The formula I ∝ 1/r^2 (where I is the intensity and r is the distance) assumes that the wave energy spreads out uniformly in three-dimensional space (A), the medium through which the wave travels is homogeneous, meaning its properties do not change from one location to another (B), and the medium does not absorb the wave energy (C). Therefore, all the given options are assumptions for the formula, making "none of the above" the correct choice.

The Intensity I of a Wave Is Related to the Distance