Sound Class 8 Quiz Question with Answer
Sound Class 8 Quiz Question with Answer. CBSE Class 8 Science Lesson 13 Mock Test.
1) Which of the following statements is incorrect?
A) Tabla is a musical instrument
B) Shriller sound has more frequency
C) Man cannot hear sound of bats
D) The sound could not travel in solid
Solution: (D) The sound could not travel in solid
Explanation: all statements are correct except only option (D) hence, that’s the solution.
2) Sound of frequency lower than 20 Hz is called___
A) Infrasonic
B) Noise
C) Ultrasonic
D) None of these
Solution: (A) Infrasonic
Explanation:: if a frequency of sound is lower than 20 hz then it is called intrasonic, hence answer will be option (A).
3) Sound of frequencies higher than 20,000 Hz are called
A) Intrasonic
B) Ultrasonic
C) Both (A) and (B)
D) None of these
Solution: (B) Ultrasonic
Explanation:: if the sound of frequencies is higher than 20,000 Hz are called ultrasonic, hence option [B] is correct answer.
4) Frequencies of ultrasonic sound is _______.
A) 2000 Hz
B) 20000 Hz
C) 10000 Hz
D) 25000 Hz
Solution: (B) 20000 Hz
Explanation:: sound of frequencies in ultrasonic is higher than 20,000 Hz
5) Infrasonic frequencies of sound is ___________20 Hz
A) Higher
B) Lower
C) Moderate
D) None of these
Solution: (B) Lower
Explanation:: sound of frequencies of sound is lower than 20 Hz then it is infrasonic frequencies, hence your answer will be option (B)
6) Too much noise in our surrounding that causes discomfort is called _____
A) Water pollution
B) Air pollution
C) Noise pollution
D) All of the above
Solution: (C) Noise pollution
Explanation:: too much noise in our surrounding that causes discomfort is called “noise pollution”
7) The speed of sound is maximum in
A) Solid
B) Liquid
C) Gaseous
D) All of these
Solution: (A) Solid
Explanation:: sound travels fastest in solid and slowest in air because the particles in solid are closer together than the liquid or gas therefore, the speed of sound is maximum solid.
8) What is the frequencies of human ear hearing
a) 20-20000 Hz
b) 10 – 10000 Hz
c) 30 – 30000 Hz
d) 40 – 40000 Hz
Solution: (A) 20-20000 Hz
Explanation:: the hearing range of human ears is 20 Hz to 20000 Hz.
9) Which of the following is responsible for producing sound in human being?\
A) Mouth
B) Tongue
C) Teeth
D) larynx
Solution: (D) larynx
Explanation: larynx is a voice box of human being, hence sound can produced in larynx, so larynx is responsible for producing sound in human being.:
10) Which of the following is a characteristic of sound?
A) Frequency
B) Amplitude
C) Waveform
D) All of these
Solution: (D) All of these
Explanation: Here, all are the properties of sound, sound is a wave. The frequency, amplitude and wave form all have properties to attribute any wave, these attributes are four elements that are frequency, amplitude, wave form and duration, hence option (D) is the solution.
11) Example of unpleasant sounds?
A) Hadida’s
B) Cats fighting
C) Cars hooting’
D) All of these
Solution: (D) All of these
Explanation: all of these sound is unpleasant sound, the frequency of this sound is between, 2,000 – 5000 Hz frequencies in this frequencies intrinsically unpleasant.
12) In which gas speed of sound is maximum?
A) Oxygen
B) Hydrogen
C) Helium
D) None of these
Solution: (B) Hydrogen
Explanation: speed of sound is maximum in hydrogen gas, because hydrogen gas is lightest with molecular mass of Lu and Oxygen being the heaviest with molecular mass of Helium and oxygen. Hence, sound velocity will be maximum in hydrogen.
13) Does sound travel faster in vacuum than air?
A) Yes
B) No
C) Can’t say
D) None of these
Solution: (B) No
Explanation: the speed of sound is zero in vacuum, as sound cannot travel in vacuum, the speed of sound in air mainly depends on the temperature of the air, it is about 343 metre per second, which is faster than the speed of sound in a vacuum.
14) Unpleasant sound is also called?
A) Noise
B) Euphonious
C) Both (A) and (B)
D) None of these
Solution: (A) Noise
Explanation: unpleasant sound is also called noise.
15) Which Examples of pleasant sound?
A) The sound of rain
B) A cracking fire
C) A golf ball going in the hole
D) All of these
Solution: (D) All of these
Explanation: all of these sounds are pleasant because they make people feel happy.
16) Choose the incorrect pair?
A) Normal breathing – 10dB
B) Frequency – Hertz
C) Pleasant sound – Noise
D) Tabla – Percussion instrument
Solution: (C) Pleasant sound – Noise
Explanation: Out of the given option, option (C) is incorrect because noise is not a pleasant sound, it’s irritating to hearing people.
17) In which of the following state a sound can be travel?
A) Solid
B) Liquid
C) Gaseous
D) All of these
Solution: (D) All of these
Explanation: a sound can travel through solid, liquid and gaseous. Hence, the answer will be option [D].
18) Which of the following waves travel in the air?
A) Transverse wave
B) Longitudinal wave
C) Polarised wave
D) None of these
Solution: (B) Longitudinal wave
Explanation: longitudinal waves travel in the air.
19) Sound is expressed in which of the following unit?
A) Metre
B) Unit-less
C) Second
D) hertz
Solution: (D) hertz
Explanation: sound is expressed in hertz.