A police car is moving in your direction, constantly accelerating, with its siren on. As it gets closer, the sound you hear will a) stay at the same frequency. b) drop in frequency. c) increase in frequency. d) More information is needed.

Short Answer

Expert verified
Answer: c) increase in frequency

Step by step solution

01

Understand the Doppler Effect

The Doppler Effect is a phenomenon that occurs when the frequency and wavelength of a wave (in this case, a sound wave) change due to the relative motion between the source of the wave and the observer. When the source of the sound is moving towards the observer, the observed frequency increases, while if it is moving away, the observed frequency decreases.
02

Apply the Doppler Effect to a moving sound source

In this exercise, the police car is moving towards the observer (listener) with constant acceleration. Due to the Doppler Effect, the observed frequency of the sound waves from the siren will get compressed, resulting in a higher frequency than the emitted frequency as the car gets closer.
03

Choose the correct answer

Considering our understanding of the Doppler Effect and the behavior of sound waves, the correct answer for this exercise is: c) increase in frequency.

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