Q14.The engine of a train moving with speed 10 m s−1 towards a platform sounds a whistle at frequency 400 Hz . The frequency heard by a passenger inside the train is: (Neglect air speed. Speed of sound in air = 330 m s−1 ) (1) 400 Hz (2) 200 Hz (3) 412 Hz (4) 388 Hz
What This Question Tests
This question applies the Doppler effect formula to calculate the observed frequency when both the source and observer are in motion, with specific attention to the signs for relative velocities.
Concepts Tested
Formulas Used
f' = f((v ± v_o) / (v ± v_s))
📚 NCERT Sections This Tests
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📋 Question Details
- Chapter
- Waves & Sound
- Topic
- Doppler Effect
- Year
- 2023
- Shift
- 08 Apr Shift 1
- Q Number
- Q14
- Type
- MCQ
- NCERT Ref
- Class 11 Physics Ch 15: Waves
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