Question:

On the same path, the source and observer are moving such that the distance between them increases with time. The speeds of the source and observer are the same and equal to 10 m/s with respect to the ground, and no wind is blowing. If the apparent frequency received by the observer is 1950 Hz, what is the original frequency?

2068Hz

2100Hz

602Hz

1903Hz

Correct option is A. 2068Hz

Since they both move with speed 10 m/s and the distance between them increases with time, they must definitely be moving away from each other.

Hence the apparent frequency received by the observer = f₀(c - v₀)/(c + vₛ) => f₀(340 - 10)/(340 + 10) = 1950 Hz => f₀ = 2068 Hz