Q12.A submarine A travelling at 18km hr-1 is being chased along the line of its velocity by another submarine B travelling at 27 km hr-1 . B sends a sonar signal of 500 Hz to detect A and receives a reflected sound of frequency v. The value of v is closed to (Speed of sound in water 1500 m s-1 ) (1) 504 Hz (2) 499 Hz (3) 502 Hz (4) 507 Hz
What This Question Tests
This question involves a double Doppler effect calculation: first for the sound reaching the target submarine, and then for the reflected sound returning to the source, requiring careful consideration of relative velocities.
Concepts Tested
Formulas Used
f' = f [(v ± v_observer) / (v ± v_source)]
📚 NCERT Sections This Tests
14.6 — Reflection Of Waves
Physics Class 12 · Chapter 14
14.6 Reflection of waves some cork pieces on the disturbed surface, it is seen that
12.6 — (A) 2.18 × 106 M/S; 1.09 × 106 M/S; 7.27 × 105 M/S
Physics Class 12 · Chapter 12
12.6 (a) 2.18 × 106 m/s; 1.09 × 106 m/s; 7.27 × 105 m/s (b) 1.52 × 10–16 s; 1.22 × 10–15 s; 4.11 × 10–15 s.
10.1 — Monochromatic Light Of Wavelength 589 Nm Is Incident From Air On A
Physics Class 12 · Chapter 10
10.1 Monochromatic light of wavelength 589 nm is incident from air on a water surface. What are the wavelength, frequency and speed of (a) reflected, and (b) refracted light? Refractive index of water is 1.33.
📋 Question Details
- Chapter
- Waves & Sound
- Topic
- Doppler effect in sound
- Year
- 2019
- Shift
- 12 Apr Shift 1
- Q Number
- Q12
- Type
- MCQ
- NCERT Ref
- Class 11 Physics Ch 15: Waves
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