Chapter 11
Sound
Encircle the most appropriate answer from the following options :
1, The study of sound is called
(a) Acoustic
(b) Optics
(c) Electrostatics
(d) All of these
2. Sound is produced by
(a) Propagation
(b) Vibration
(c) Both of these
(d) None of these
3. Sound can travel only in presence of
(a) Medium
(b) vacuum
(c) Air
(d) Both a and c
4. Sound is Wave
(a) Electromagnetic
(b) Transverse
(c) Longitudinal
(d) None of these
5. Characteristic by which We can differentiate two sounds of same loudness and pitch is called
(a) Loudness
(b) Pitch
(c) Quality
(d) intensity of sound
6. Pitch of sound depends on
(a) Amplitude
(b) frequency
(c) time period
(d) Displacement
7. Distance between two consecutive compressions and rarefactions is the sound wave.
(a) Amplitude
(b) Frequency
(c) Wave Length
(d) none of these
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8. Loudness of sound depends on
(a) Amplitude of vibrating body
(b) Area of vibrating body
(c) Distance of vibrating body
(d) All Of these
9. is the characteristic of sound by which we will distinguish between a shrill and a grave sound.
(a) Pitch
(b) loudness
(c) intensity
(d) quality
10. Frequency of silent whistle Lies between
(a) 20,000Hz – 25,000Hz
(b) 20,000Hz – 35,000Hz
(c) 20Hz – 20,OOOHz
(d) 15000Hz – 40,000Hz
11. The intensity of sound depends on the
(a) Time period
(b) frequency
(c) Amplitude
(d) None of these
12. Intensity is a quantity.
(a) Vector
(b) Scalar
(c) Physical quantity
(d) None of these
13. Intensity of faintest sound is
(a). 1012 Wm-2
(b) 10-12Wm-2
(c) 10-8Wm-2
(d) 10-9Wm-2
14. Researcher in observed giraffes to stop and waitTor the others that were out of sight
(a) 1898
(b) 1993
(c)2013
(d) None of these
15. Bats can hear frequency up to
(a) 120, 000Hz
(b) 2,000 Hz
(c) 20, 000 Hz
(d) 15,000 Hz
16. The loudness of sound is directly proportional to loéarithm of intensity, this Law is called
(a) Weber Fechner Law
(b) Law of Gravitation
(c) Intensity Level
(d) Echo
17. Voice of Child is
(a) Grave
(b) Shrill
(c) Faint
(d) Loud
18. I bell is equal to
(a) 20dB
(b) 10dB
(c) I00dB
(d) 50dB
19. The amplitude of 100 dB sound is
(a) 1000
(b) 10,000
(c) I00, 000
(d) 1001000
20. By using an__we can see sound waves.
(a) Electroscope
(b) stroboscope
(c) Gastroscope
(d) oscilloscope
21. Echo of sound is
(a) Refraction
(b) Reflection
(c) Diffraction
(d) Interference
22. The sensation of sound persists in our brain about
(a) 1 s
(b) 0.1 s
(c) 0.01s
(d) 2s
23. For hearing distinct echoes, the minimum distance of obstacle from source of source of sound must be
(a) 34 m
(b) 17 m
(c) 38m
(d) 16m
24. The speed of sound in solid is about times that in gases.
(a) 5
(b) 15
(c) 20
(d) 10
25. The speed of sound in air at a2 atm pressure and at room temperature (21°C) is
(a) 320ms-1
(b) 360m/s
(c) 343ms-1
(d) None of these
26. The speed of sound varies with
(a) Temperature
(b) Humidity
(c) both a and b
(d) None of these than liquid and air
27. The speed of sound in solid is
(a) Greater
(b) Sinaller
(c) Equal
(d) None of these
28. Bats can hear Frequencies up to 120,000Hz
(a) I0, 000Hz
(b) 120,000Hz
(c) 1 2,00,000Hz
(d) 120,00,000Hz
29. Mice can hear frequencies up to
(a) 35,00Hz
(b) 35,000Hz
(c) 45,00Hz
(d) 100,000 Hz
30. Compressions are places Where air is slightly than the surrounding air
(a) Less
(b) Higher
(c) Equal
(d) None of these
31. Rarefactions are places where air is slightly ___ than the surrounding air
(a) Less
(b) Higher
(c) Equal
(d) None of these
32. The speed of sound in air was first accurately measured in
(a) 1838
(b) 1738
(c) 1638
(d) 1938
33. Such sound Which are pleasant to our ears are called
(a) Musical Sound
(b) Noise
(c) Both a and b
(d) None of these
34. Such sounds which are unpleasant to our ears are Called
(a) Musical Sound
(b) Noise
(c) Both a and b
(d) None of these
35. Corresponds to irregular and sudden vibrations-produced by some sound
(a) Noise
(b) Musical- Sound
(c) Notes of tuning fork
(d) None of these
36. The Level of noise in most countries is recommended
(a) 75-80dB
(b) 85-90dB
(c) 95-100dB
(d) 115-120dB
37. The method used to absorb undesirable sound by soft and porous surface is called
(a) Acoustics
(b) Echos
(c) Intensity
(d) Pitclu
38. Multiple reflections called
(a) Acoustics
(b) reverberations
(c) Vibration
(d) All of these
39. We hear sound produce by muSical instrument-such as
(a) Flute
(b) Violin
(c) Harmomc
(d) All of these
40. For a normal person audible frequency range for sound wave lie between
(a) 10th and 10 Khz
(b) 20 Hz and 20KHz
(c) 25Hz and 25 KHz
(d) 30Hz and 30 KHz
41. Noise correspond vibration
(a) Irregular
(b) Sudden
(c)Both a and ‘b’
(d) Slowly slowly
42. Noise has negative effects on human health it cause except
(a) Aggression
(b) Hypertension
(c) stress level
(d) Fever/flu
43. Which are the acoustic protection except
(a) Lecture Halls
(b) Auditorium
(c) Theater halls
(d) Kitchen
44. Audible frequency range is
(a) 200Hz-2000Hz
(b) 15Hz-15000Hz
(c) 20Hz-20KHz
(d) None of these
45. Old people cannot hear sound even above
(a) 20, OOHz
(b) 15 KlHz
(c) 15,000 Hz
(d) Both (b) and (c)
46. Which bird fly easily between wires in the black room
(a) Sparrow
(b) Bat
(c) Cow
(d) Parrot
47. The range of the frequency which human, ear can hear is called
(a) Audible frequency range
(b) Ultrasonic waves
(c) Transonic waves
(d) None of these
48. Sound waves with frequency less than 20Hz are called
(a) Ultrasonic
(b) Infrasonics
(c) Notes
(d) Acoustic
49. Ultrasound is the frequency of sound higher than
(a) 20Hz
(b) 20KHz
(c) 15,000 Hz
(d) 25,000 1-Iz
50. Infrasonic is the frequency of sound less thin
(a) 20Hz
(b) 20 KHz
(c) 15,000 Hz
(d) 25,000 Hz