Q16.A train blowing a whistle of frequency 320 Hz approaches an observer standing on the platform at a speed of 66 m s−1 . The frequency observed by the observer will be (given speed of sound = 330 m s−1 ) ______ Hz.
What This Question Tests
This question applies the Doppler effect formula for sound to calculate the observed frequency when a source approaches a stationary observer.
Concepts Tested
Formulas Used
f' = f ((v ± v_o) / (v ∓ v_s))
📚 NCERT Sections This Tests
12.3 — A Difference Of 2.3 Ev Separates Two Energy Levels In An Atom. What
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12.3 A difference of 2.3 eV separates two energy levels in an atom. What is the frequency of radiation emitted when the atom make a transition from the upper level to the lower level?
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12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
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📋 Question Details
- Chapter
- Waves & Sound
- Topic
- Doppler Effect
- Year
- 2023
- Shift
- 25 Jan Shift 2
- Q Number
- Q16
- Type
- Numerical
- NCERT Ref
- Class 11 Physics Ch 15: Waves
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