Question:medium
A train sounds its whistle as it approaches an observer standing at a point near the track. The observer measures a frequency of $216$ Hz as the train approaches and a frequency of $184$ Hz as the train leaves. What is the frequency of its whistle?
A train sounds its whistle as it approaches an observer standing at a point near the track. The observer measures a frequency of $216$ Hz as the train approaches and a frequency of $184$ Hz as the train leaves. What is the frequency of its whistle?
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In many school-level Doppler problems where $v_s$ is small compared to $v$, the source frequency is roughly the average of the approaching and receding frequencies!
Updated On: May 1, 2026
- $210$ Hz
- $190$ Hz
- $205$ Hz
- $202$ Hz
- $200$ Hz
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The Correct Option is
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