Question

A passenger is sitting in a fast moving train. The engine of the train blows a whistle of frequency N. If the apparent frequency of sound heard by the passengers is \( N' \), then:

• A. \( N' = N \)
• B. \( N' < N \)
• C. \( N' > N \)
• D. \( N' N = 1 \)

Hint:

In the case of a passenger sitting in a moving train, the apparent frequency heard is unaffected by the motion of the train.

Answer 1

The Correct Option is A

The observed sound frequency for passengers is determined by the relative motion between the sound source and the observer. As the passengers are moving with the train, they experience the same frequency as emitted by the whistle, \( N' = N \).