SoundCopy
1. Which of the following best describes sound waves in air?
A) Transverse, mechanical
B) Longitudinal, mechanical
C) Transverse, electromagnetic
D) Longitudinal, electromagnetic
2. Which property of sound increases when the amplitude of vibration increases?
A) Pitch
B) Frequency
C) Speed
D) Loudness
3. The range of human hearing is approximately:
A) 20 Hz – 200 kHz
B) 20 Hz – 20 kHz
C) 2 Hz – 200 Hz
D) 200 Hz – 20 kHz
4. What happens to the speed of sound as it travels from air into steel?
A) It decreases
B) It remains constant
C) It increases
D) It becomes zero
5. In a sound wave, compressions and rarefactions are:
A) Regions of constant pressure
B) Alternating regions of high and low pressure
C) Points of zero displacement
D) Crests and troughs
6. The wavelength of a 440 Hz sound in air (speed = 330 m/s) is:
A) 0.75 m
B) 1.33 m
C) 0.48 m
D) 1.52 m
7. In which of the following does sound travel fastest?
A) Vacuum
B) Water
C) Steel
D) Air
8. The function of the ear drum is to:
A) Produce sound
B) Detect electromagnetic waves
C) Vibrate with incoming sound waves
D) Amplify light waves
9. What happens when the amplitude of a sound wave doubles?
A) Frequency doubles
B) Pitch increases
C) Loudness increases
D) Wavelength doubles
10. If a sound wave has a frequency of 1000 Hz and a wavelength of 0.34 m, its speed is:
A) 340 m/s
B) 3.4 m/s
C) 0.34 m/s
D) 100 m/s
11. Which term best describes the reflection of sound?
A) Echo
B) Refraction
C) Reverberation
D) Diffraction
12. Reverberation is most likely to occur in:
A) Vacuum
B) Open field
C) Tightly furnished room
D) Large hall with hard surfaces
13. Which physical quantity is unchanged when sound passes into a different medium?
A) Wavelength
B) Speed
C) Frequency
D) Direction
14. Which feature determines the pitch of a note?
A) Amplitude
B) Frequency
C) Wavelength
D) Phase
15. If the wavelength of a sound is 2.5 m and its frequency is 220 Hz, its speed is:
A) 528 m/s
B) 550 m/s
C) 440 m/s
D) 220 m/s
16. Ultrasound is defined as sound with frequency:
A) Above 20 Hz
B) Above 200 Hz
C) Above 20 kHz
D) Below 20 Hz
17. Which application uses ultrasound?
A) X-ray imaging
B) Doppler radar
C) Sonar mapping
D) MRI scan
18. A longitudinal wave is one in which particle motion is:
A) Perpendicular to wave motion
B) In circular paths
C) Along the direction of wave motion
D) Oscillating randomly
19. Which of the following affects the speed of sound in air?
A) Frequency
B) Pitch
C) Temperature
D) Loudness
20. A sound wave with larger amplitude compared to another has:
A) Higher pitch
B) Lower speed
C) Greater energy
D) Lower frequency
21. Why can’t sound travel through vacuum?
A) Sound waves are transverse
B) Particles in vacuum vibrate freely
C) No particles to carry vibrations
D) Sound travels only through liquids
22. In an oscilloscope display, what does a taller waveform indicate?
A) Higher frequency
B) Higher pitch
C) Greater amplitude
D) Lower wavelength
23. Two tuning forks of same frequency sound different due to:
A) Pitch
B) Loudness
C) Quality (timbre)
D) Wavelength
24. Which of these statements is true for sound?
A) Travels faster in gas than solid
B) Does not reflect
C) Is an electromagnetic wave
D) Transfers energy but not matter
25. Which factor is most responsible for sound diffraction?
A) Frequency
B) Surface temperature
C) Speed
D) Wavelength
26. If a wave travels 660 m in 2 seconds, its speed is:
A) 132 m/s
B) 330 m/s
C) 660 m/s
D) 165 m/s
27. Echoes are produced when:
A) Sound is absorbed
B) Sound travels through a medium
C) Sound reflects off surfaces
D) Sound changes pitch
28. What is the effect of increasing the frequency of a sound wave while keeping speed constant?
A) Wavelength increases
B) Amplitude increases
C) Wavelength decreases
D) Speed increases
29. Which sound wave property allows bats to locate insects?
A) Refraction
B) Polarisation
C) Echo location
D) Reverberation
30. Sound waves are produced when:
A) A body moves linearly
B) There is heat radiation
C) An object vibrates
D) An electric field oscillates
31. The note produced by a tuning fork is:
A) Complex waveform
B) Pure sine wave
C) Square waveform
D) Triangle waveform
32. Which wave property is responsible for identifying different voices?
A) Loudness
B) Speed
C) Pitch
D) Quality
33. The ratio of the pressure in a compression to that in rarefaction is called:
A) Wavelength
B) Frequency
C) Pressure ratio
D) Amplitude
34. What makes two sounds of same pitch and loudness different?
A) Frequency
B) Quality
C) Amplitude
D) Wavelength
35. Sonar systems work by:
A) Reflecting light
B) Detecting magnetic fields
C) Measuring time delay of sound echo
D) Analyzing temperature changes
1. ✅ B) Longitudinal, mechanical
Sound needs particles → mechanical; particle motion ‖ wave direction → longitudinal
❌ A/C/D – EM waves or transverse → incorrect
2. ✅ D) Loudness
Louder sound = greater amplitude
❌ A/B – Related to frequency
❌ C – Speed depends on medium
3. ✅ B) 20 Hz – 20 kHz
This is the audible range for humans
❌ Others – Below or above human hearing
4. ✅ C) It increases
Sound travels faster in solids due to denser particle arrangement
❌ A/B/D – Incorrect medium behavior
5. ✅ B) Alternating regions of high and low pressure
Compressions = high pressure, rarefactions = low
❌ A – Not constant
❌ C – Displacement varies
❌ D – Crests/troughs = transverse
6. ✅ A) 0.75 m
λ = v/f = 330/440 = 0.75 m
❌ Others – Incorrect calculation
7. ✅ C) Steel
Solids transmit sound fastest
❌ A – No transmission
❌ B/D – Slower
8. ✅ C) Vibrate with incoming sound waves
Ear drum converts pressure waves into mechanical vibrations
❌ A/B/D – Not correct function
9. ✅ C) Loudness increases
Amplitude ∝ loudness²
❌ A/B – Frequency/pitch constant
❌ D – Wavelength unrelated
10. ✅ A) 340 m/s
v = fλ = 1000 × 0.34 = 340 m/s
❌ Others – Off by powers of 10
11. ✅ A) Echo
Echo = sound reflected and heard distinctly
❌ B – Refraction = bending
❌ C – Overlapping echoes
❌ D – Spreading
12. ✅ D) Large hall with hard surfaces
Reflective surfaces cause prolonged reflection → reverberation
❌ Others – Absorb sound or too open
13. ✅ C) Frequency
Frequency is source property; constant across mediums
❌ A/B/D – All change with medium
14. ✅ B) Frequency
Higher frequency = higher pitch
❌ A/C/D – May relate to other properties, but not pitch
15. ✅ A) 528 m/s
v = fλ = 220 × 2.4 = 528 m/s
❌ Others – Math errors
16. ✅ C) Above 20 kHz
Ultrasound > 20,000 Hz
❌ A/B/D – Too low
17. ✅ C) Sonar mapping
Sonar = using reflected ultrasound for depth/distance
❌ A/B/D – Not ultrasound-based
18. ✅ C) Along the direction of wave motion
Longitudinal = parallel vibration
❌ A – Transverse
❌ B/D – Incorrect motion
19. ✅ C) Temperature
Higher temperature = faster particle motion = faster sound
❌ Others – No direct influence
20. ✅ C) Greater energy
Energy ∝ amplitude²
❌ A/B/D – Not caused by amplitude
21. ✅ C) No particles to carry vibrations
Sound = mechanical; needs medium
❌ A – Sound is longitudinal
❌ B – Vacuum = no particles
❌ D – Can travel in solids, liquids, gases
22. ✅ C) Greater amplitude
Height on oscilloscope = amplitude
❌ A/B – Frequency = spacing
❌ D – Misinterpretation
23. ✅ C) Quality (timbre)
Timbre = waveform shape; same pitch/loudness, different sound
❌ A/B – Equal
❌ D – Equal if f constant
24. ✅ D) Transfers energy but not matter
Like all waves, sound transports energy only
❌ A – Reversed
❌ B – It reflects
❌ C – Mechanical wave, not EM
25. ✅ D) Wavelength
Longer wavelength → more diffraction
❌ A/B/C – Indirect or unrelated
26. ✅ B) 330 m/s
Speed = distance/time = 660 / 2
❌ Others – Incorrect division
27. ✅ C) Sound reflects off surfaces
Echo = reflection from hard surface
❌ A – Opposite
❌ B – Needed, but not cause
❌ D – Irrelevant
28. ✅ C) Wavelength decreases
If v constant, λ = v/f → ↑f = ↓λ
❌ A – Opposite
❌ B – Not affected
❌ D – Speed fixed
29. ✅ C) Echo location
Bats emit ultrasound, detect echoes
❌ A – No major role
❌ B – Not used in sound
❌ D – Involves overlapping
30. ✅ C) An object vibrates
Vibrations produce compressions/rarefactions
❌ A/B/D – Not correct mechanism
31. ✅ B) Pure sine wave
Tuning fork = ideal single frequency
❌ A – Multiple frequencies
❌ C/D – Square/triangle = artificial
32. ✅ D) Quality
Voice uniqueness = waveform shape
❌ A/B/C – May be same
33. ✅ D) Amplitude
Amplitude = pressure variation magnitude
❌ A/B/C – Incorrect quantities
34. ✅ B) Quality
Tone color/timbre differentiates voices
❌ A – Pitch is same
❌ C – Loudness same
❌ D – If f same, λ fixed
35. ✅ C) Measuring time delay of sound echo
SONAR = time × speed / 2
❌ A – Not light
❌ B/D – Not used