Q25.A person driving car at a constant speed of 15 m s-1 is approaching a vertical wall. The person notices a change of 40 Hz in the frequency of his car’s horn upon reflection from the wall. The frequency of horn is _______Hz . (Given: Speed of sound: 30 m s-1)
What This Question Tests
This question tests the application of the Doppler effect twice: once for the sound reaching the wall and again for the reflected sound reaching the car, to find the original frequency.
Concepts Tested
Formulas Used
f' = f * (v ± v_o) / (v ± v_s)
Δf = f'' - f
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📋 Question Details
- Chapter
- Waves & Sound
- Topic
- Doppler Effect
- Year
- 2023
- Shift
- 06 Apr Shift 1
- Q Number
- Q25
- Type
- Numerical
- NCERT Ref
- Class 11 Physics Ch 15: Waves
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