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Question
A small source of sounds moves on a circle as shown in figure and an observer is sitting at O. Let \[v_1, v_2, v_3\] be the frequencies heard when the source is at A, B and C respectively.
Options
\[v_1 > v_2 > v_3\]
\[v_1 = v_2 > v_3\]
\[v_2 > v_3 > v_1\]
\[v_1 > v_3 > v_2\]
Solution
\[v_2 > v_3 > v_1\]
At B, the velocity of the source is along the line joining the source and the observer. Therefore, at B, the source is approaching with the highest velocity as compared to A and C. Hence, the frequency heard is maximum when the source is at B.
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