Chapter 25, Problem 15A

When a wave source moves toward a receiver, does the receiver encounter an increase in wave frequency, wave speed, or both?

To determine

To identify: Whether a receiver encounters an increase in wave frequency, wave speed, or both when a wave source moves towards a receiver.

Answer to Problem 15A

There will be an increase in wave frequency.

Explanation of Solution

Introduction:

A wave travels with a constant speed if there is no medium, if medium present then the amplitude of the wave descends.

When a receiver observes a wave traveling towards him, then the intensity of the sound increases. It is because the wave frequency increasing with the decreasing distance in between. But, the wave travels with constant speed. That is less than but comparatively speed of light.

Conclusion:

Thus, while traveling towards the receiver, wave frequency increases but not the wave speed.