Maharashtra Board Class 8 Science MCQ Chapter 15 Sound
1 ) In regions called , particles are crowded together.
A ) Reverberation
B ) Compressions
C ) Rarefactions
D ) Oscillations
Ans B ) Compressions
2 ) …………… and of the movement of the coil depends on the variation of the current flowing through
the coil.
A ) Frequency and Magnetic flux
B ) Amplitude and Magnetic field
C ) Frequency and amplitude
D ) Magnetic flux and Amplitude
Ans C ) Frequency and amplitude
3 ) A bomb explodes on the moon. How long will it take for the sound to reach the earth?
A ) 10 seconds
B ) 1000 seconds
C ) 1 day
D ) None of these
Ans D ) None of these
4 ) The amplitude of vibratory motion is measured in units of
A ) Length
B ) Time
C ) Speed
D ) Hz
Ans A ) Length
5 ) If the medium is absent for the sound to travel then
A ) Sound will still travel
B ) Sound won’t travel without a medium
C ) Depends on the vibrations and the frequency of sound
D ) None of the above
Ans B ) Sound won’t travel without a medium
6 ) In a loudspeaker there is
A ) Generation of electric current inside the loudspeaker
B ) Generation of a magnetic field
C ) Generation of power
D Generation of a magnetic field
Ans Generation of a magnetic field
7 ) As the quantity of air inside the bell jar decreases, the level of ringing sound heard outside …………… .
A ) Increases
B ) Decreases
C ) Remains same
D ) Doubles
Ans B ) Decreases
8 ) Loudspeaker consists of
A ) Horseshoe magnet
B ) Permanent Magnet
C ) Bar magnet
D ) Amplifier
Ans B ) Permanent Magnet
9 ) Unit of measurement of sound is
A ) Decibel
B ) Hertz
C ) Coulomb
D ) Debye
Ans A ) Decibel
10 ) Medium is necessary for sound to propagate.
A ) True
B ) False
Ans A ) True
11 ) Increased pressure produces
A ) Rarefaction
B ) Compression
C ) Vibration
D ) Energy
Ans B ) Compression
12 ) Which of the following vibrates when a musical note is produced by the cymbals in an orchestra?
A ) Stretched strings
B ) Stretched membranes
C ) Metal plates
D ) Air columns
Ans C ) Metal plates
13 ) Tuning fork generally shows a frequency of
A)510HZ
B ) 512 Hz
C ) 521 Hz
D ) 501 Hz
Ans B ) 512 Hz
14 ) Due to back and forth motion of the of the tuning fork, sound waves are produced.
A ) Prongs
B ) Screen
C ) Stem
D ) Coil
Ans A ) Prongs
15 ) What does the vaccum pump experiment determine?
A ) Sound requires a medium to travel
B ) Sound travels by the means of waves
C ) Sound takes place due to generation of vibrations
D ) Sound is independent of the type of meduium for its travelling
Ans A ) Sound requires a medium to travel
16 ) make the vocal cords tight or loose
A ) Muscles attached to the vocal cords
B ) The vocal cords themselves
C ) Trachea
D ) Larynx
Ans A ) Muscles attached to the vocal cords
17 ) Sound cannot travel through …………… .
A ) Metal
B ) Air
C ) Water
D ) Vacuum
Ans D ) Vacuum
18 ) When the prongs come closer to each other , the pressure
A ) Decreases
B ) Increases
C ) First increases then decreases
D ) First decreases then increases
Ans A ) Decreases
19 ) When the air outside the prongs is compressed the pressure
A ) Decreases
B ) Increases
C ) First increases then decreases
D ) First decreases then increases
Ans B ) Increases
20 ) A rapid periodic forward aagnadinb.ackward motion of an object is called …………… .
A ) Sound
B ) Acceleration
C ) Intensity
D ) Vibration
Ans D ) Vibration
21 ) The maximum displacement of a particle in a vibratory motion is known as
A ) Time period
B ) Wavelength
C ) Amplitude
D ) Frequency
Ans C ) Amplitude
22 ) Sound is produced by
A ) Waves
B ) Energy
C ) Vibrations
D ) Heat
Ans C ) Vibrations
23 ) How many vocal cords are present in a human?
A ) 1
B ) 2
C ) 3
D ) 4
Ans B ) 2
24 ) Vibration of air column produces sound in which of the following instruments?
A ) Jaltaranga
B ) Flute
C ) Siren
D ) All of the above
Ans D) All of the above
25) Hertz is theunit of :
A ) Wavelength B ) Amplitude C ) Frequency
D ) None of these
Ans C ) Frequency
25 ) Above what level the sound can be harmful to the human ears?
A ) 500 decibels
B ) 200 decibels
C ) 100 decibels
D ) 150 decibels
Ans C ) 100 decibels
26 ) In string based instruments, the frequency of vibration of the string is changed by
A ) Changing the tension on the string
B ) By changing the vibrating length of the string using fingers.
C ) By changing the number of strings
D ) All of the above
Ans D ) All of the above
27 ) The prongs of a tuning fork
A ) Set into periodic motion in forward and backward direction
B ) Vibrate when struck
C ) Vibrate when they are provided with heat
D ) Both 1 and 2
Ans D ) Both 1 and 2
28 ) In humans sound is produced in the
A ) Pharynx
B ) Larynx
C ) Trachea
D ) Vocal cord
Ans B ) Larynx
29 ) The voices of men, women and children are different due to difference in:
A ) Larynx
B ) Lungs
C ) Vocal coards
D ) Wind pipe
Ans C ) Vocal coards
30 ) Which of the following cannot travel through vacuum?
A ) Light waves
B ) Heat waves
C ) X-rays
D ) Sound waves
Ans D ) Sound waves
31 ) The frequency of the prongs is not dependent of
A ) Mass of prong
B ) Thickness of Prong
C ) Length of Prong
D ) Material of the prong again.
Ans A ) Mass of prong
