Chapter 12: Sound & Hearing - Science Mcqs for Grade 8 - Set 2

1)   The SI unit of frequency is

a. hertz
b. Newton
c. Pascal
d. ampere
Answer  Explanation 

ANSWER: hertz

Explanation:
No explanation is available for this question!


2)   The regions where molecules spread out are called

a. rarefactions
b. compressions
c. digressions
d. progressions
Answer  Explanation 

ANSWER: rarefactions

Explanation:
No explanation is available for this question!


3)   An instrument which can produce a number a sounds with high and low frequencies and pitch is the

a. violin
b. piano
c. guitar
d. double bass
Answer  Explanation 

ANSWER: piano

Explanation:
No explanation is available for this question!


4)   Ultrasound and infrasound are not detected by

a. humans
b. animals
c. birds
d. all of them
Answer  Explanation 

ANSWER: all of them

Explanation:
No explanation is available for this question!


5)   A measure of amount of energy in a sound wave is called its

a. wavelength
b. frequency
c. amplitude
d. all of them
Answer  Explanation 

ANSWER: amplitude

Explanation:
No explanation is available for this question!


6)   He symbol of decibel is

a. Dc
b. dB
c. Dec
d. dl
Answer  Explanation 

ANSWER: dB

Explanation:
No explanation is available for this question!


7)   Humans can hear the sound with in range

a. 20Hz - 20000Hz
b. 10Hz-10000Hz
c. 200Hz-20000Hz
d. 30Hz--30000Hz
Answer  Explanation 

ANSWER: 20Hz - 20000Hz

Explanation:
No explanation is available for this question!


8)   The brain interprets vibrations and electrical signals as

a. sounds
b. actions
c. reactions
d. movements
Answer  Explanation 

ANSWER: sounds

Explanation:
No explanation is available for this question!


9)   The vibrations in stirrup are greater than ear drum due to arrangement in

a. lever like manner
b. ascending manner
c. descending manner
d. jointed manner
Answer  Explanation 

ANSWER: lever like manner

Explanation:
No explanation is available for this question!


10)   A pitch of sound can be change by changing

a. string
b. instrument
c. tension
d. temperature
Answer  Explanation 

ANSWER: tension

Explanation:
No explanation is available for this question!