Waves and Sound MCQs
Waves and Sound MCQs – CBSE Class 11 Physics
Class: 11
Subject: Physics
Section: Oscillations and Waves
Topic: Waves and Sound
Board: CBSE Board Examination (NCERT Based)
Subject: Physics
Section: Oscillations and Waves
Topic: Waves and Sound
Board: CBSE Board Examination (NCERT Based)
Q1. A wave that requires a material medium for propagation is called:
Answer: B) Mechanical wave
Mechanical waves like sound need a medium because energy transfer occurs through particle vibrations.
Mechanical waves like sound need a medium because energy transfer occurs through particle vibrations.
Q2. SI unit of wavelength is:
Answer: B) Metre
Wavelength is a measure of distance between two consecutive crests or compressions.
Wavelength is a measure of distance between two consecutive crests or compressions.
Q3. Relation between wave speed (v), frequency (f) and wavelength (λ):
Answer: B) v = fλ
Wave speed equals product of frequency and wavelength — fundamental wave relation.
Wave speed equals product of frequency and wavelength — fundamental wave relation.
Q4. Sound waves in air are:
Answer: B) Longitudinal
Particles vibrate parallel to wave propagation, forming compressions and rarefactions.
Particles vibrate parallel to wave propagation, forming compressions and rarefactions.
Q5. Frequency is measured in:
Answer: B) Hz
1 Hertz = 1 oscillation per second.
1 Hertz = 1 oscillation per second.
Q6. Speed of sound is maximum in:
Answer: C) Solids
Higher elasticity → faster sound transmission.
Higher elasticity → faster sound transmission.
Q7. Audible range for humans:
Answer: B) 20–20,000 Hz
Below → Infrasonic, Above → Ultrasonic.
Below → Infrasonic, Above → Ultrasonic.
Q8. Echo is produced due to:
Answer: B) Reflection
Sound reflects from distant surfaces producing echo.
Sound reflects from distant surfaces producing echo.
Q9. Minimum distance to hear echo distinctly:
Answer: C) 17 m
Persistence of hearing ≈ 0.1 s → distance ≈ 17 m.
Persistence of hearing ≈ 0.1 s → distance ≈ 17 m.
Q10. Unit of sound intensity:
Answer: A) Watt/m²
Intensity = Power/Area.
Intensity = Power/Area.
Q11. Loudness depends on:
Answer: B) Amplitude
Greater amplitude → louder sound.
Greater amplitude → louder sound.
Q12. Pitch depends on:
Answer: B) Frequency
Higher frequency → higher pitch.
Higher frequency → higher pitch.
Q13. Doppler effect relates to change in:
Answer: B) Frequency
Relative motion changes observed frequency.
Relative motion changes observed frequency.
Q14. Beats are formed due to:
Answer: B) Interference
Two close frequencies interfere producing beats.
Two close frequencies interfere producing beats.
Q15. Number of beats per second equals:
Answer: B) Difference between frequencies.
Q16. Wave motion transfers:
Answer: B — Energy propagates, not matter.
Q17. Crest is found in:
Answer: B — Crest = max displacement.
Q18. Compression occurs in:
Answer: B
Q19. Time period =
Answer: A
Q20. Ultrasonic waves frequency:
Answer: C
Q21. SONAR uses:
Answer: B
Q22. Reverberation means:
Answer: B
Q23. Unit of loudness:
Answer: B
Q24. Speed of sound increases with:
Answer: A
Q25. Standing waves form due to:
Answer: B
Q26. Nodes have:
Answer: B
Q27. Antinodes have:
Answer: B
Q28. Musical sound is:
Answer: B
Q29. Noise is:
Answer: C
Q30. Shock waves travel:
Answer: C
Shock waves move faster than sound (supersonic speeds).
Shock waves move faster than sound (supersonic speeds).