JEE Mains 06-Sep-2020 Shift 1 Solved Paper

A sound source S is moving along a straight track with speed v, and is emitting sound of frequency v0 (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 :
(t‌0 represents the instant when the distance between the source and observer is minimum)