Q24.When a car is approaching the observer, the frequency of horn is 100 Hz. After passing the observer, it is 50 Hz. If the observer moves with the car, the frequency will be x3 Hz where x =_____ .
What This Question Tests
This question applies the Doppler effect for sound to calculate the source's actual frequency and speed from observed frequencies when approaching and receding.
Concepts Tested
Formulas Used
f' = f₀ * (v ± v_o) / (v ± v_s)
📚 NCERT Sections This Tests
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
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.
12.3 — A Difference Of 2.3 Ev Separates Two Energy Levels In An Atom. What
Physics Class 12 · Chapter 12
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?
10.5 — In Young’S Double-Slit Experiment Using Monochromatic Light Of
Physics Class 12 · Chapter 10
10.5 In Young’s double-slit experiment using monochromatic light of wavelength l, the intensity of light at a point on the screen where path difference is l, is K units. What is the intensity of light at a point where path difference is l/3?
📋 Question Details
- Chapter
- Waves & Sound
- Topic
- Doppler Effect
- Year
- 2022
- Shift
- 26 Jul Shift 1
- Q Number
- Q24
- Type
- Numerical
- NCERT Ref
- Class 11 Physics Ch 15: Waves
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