# A sound source S is moving along a straight track with speed v, and is emitting sound of frequency v o (see figure). An observer is standing at a finite distance, at the point O, from the track. The time variation of frequency heard by the observer is best represented by:(t 0 represents the instant when the distance between the source and observer is minimum)

Question:

A sound source $S$ is moving along a straight track with speed $v$, and is emitting sound of frequency $v_{\mathrm{o}}$ (see figure). An observer is standing at a finite distance, at the point $O$, from the track. The time variation of frequency heard by the observer is best represented by:$\left(t_{0}\right.$ represents the instant when the distance between the source and observer is minimum)

Correct Option: 2

Solution:

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