Q22.A whistle producing sound waves of frequencies 9500 Hz and above is approaching a stationary person with speed v ms−1 . The velocity of sound in air is 300 ms−1 . If the person can hear frequencies upto a maximum of 10, 000 Hz, the maximum value of v upto which he can hear the whistle is (1) 30 ms−1 (2) 15√2 ms−1 (3) 15/√2 ms−1 (4) 15 ms−1
What This Question Tests
This question applies the Doppler effect formula for a source approaching a stationary observer to find the maximum speed of the source for a specific frequency range to be audible.
Concepts Tested
Formulas Used
f' = f₀ * (v_sound / (v_sound - v_source))
📚 NCERT Sections This Tests
11.8 — Light Of Frequency 7.21 × 1014 Hz Is Incident On A Metal Surface.
Physics Class 12 · Chapter 11
11.8 Light of frequency 7.21 × 1014 Hz is incident on a metal surface. Electrons with a maximum speed of 6.0 × 105 m/s are ejected from the surface. What is the threshold frequency for photoemission of electrons?
10.3 — (A) The Refractive Index Of Glass Is 1.5. What Is The Speed Of Light In
Physics Class 12 · Chapter 10
10.3 (a) The refractive index of glass is 1.5. What is the speed of light in glass? (Speed of light in vacuum is 3.0 × 108 m s–1) (b) Is the speed of light in glass independent of the colour of light? If not, which of the two colours red and violet travels slower in a glass prism?
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14.4 The speed of a travelling a circle. If you continue dropping pebbles in the pond, you wave see circles rapidly moving outward from the point where the
📋 Question Details
- Chapter
- Waves & Sound
- Topic
- Doppler Effect
- Year
- 2006
- Shift
- Unknown
- Q Number
- Q22
- Type
- MCQ
- NCERT Ref
- Class 11 Physics Ch 15: Waves
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