If you were to reduce the frequency of a wave on a string by a factor of 2 while keeping the speed and amplitude of the wave constant,the rate at which energy is delivered by the wave would
A)double.
B)quadruple.
C)be reduced 50%.
D)be reduced to 25% of its previous value.
E)be unchanged.

Question

Quizplus · Accepted Answer

The energy of a wave is proportional to the square of the frequency. Therefore, reducing the frequency by a factor of 2 would reduce the energy by a factor of 4 (2^2). This means that the rate at which energy is delivered by the wave would also be reduced by a factor of 4, or to 25% of its previous value. Therefore, the correct answer is D.

If You Were to Reduce the Frequency of a Wave