Question

Another Doppler Effect Equation (given on AAMC)

a) f' = f(v + v_s) / (v - v_0)
b) f' = f(v - v_s) / (v + v_0)
c) f' = f(v + v_0) / (v - v_s)
d) f' = f(v - v_0) / (v + v_s)

Answer 1

The Doppler Effect is a phenomenon where the frequency observed changes when the source and observer are in relative motion. The correct formula to use depends on whether the source is moving toward or away from the observer, with the signs within the formula changing accordingly.

Step-by-step explanation:

The Doppler Effect is a change in the observed frequency of a sound due to the relative motion between the source and the observer. In the context of the Doppler effect, the observer's frequency (fobs) can be calculated using the following formula: fobs = fs(v + vobs) / (v ± vs). Positive (+) is used when the source is moving toward the observer and negative (-) when the source is moving away. This formula accommodates both scenarios by adjusting the sign based on the direction of the source's movement relative to the observer.

Referring to the options given, the correct formula for the Doppler effect when considering the signs based on the source's direction of movement would be: f' = f(v - v0) / (v + vs) when the source is moving toward the observer and f' = f(v + v0) / (v - vs) when the source is moving away. Here, v is the speed of sound in the medium, vs is the velocity of the source, and v0 is the velocity of the observer.