Chapter 23: Sound Waves - Science Mcqs for Grade 7 - Set 2

1)   Vibrations are caused due to

a. change of temperature of air
b. change of pressure in air
c. effect of humidity on air
d. level of heat in air
Answer  Explanation 

ANSWER: change of pressure in air

Explanation:
No explanation is available for this question!


2)   The only thing of a note that can vary, is

a. amplitude
b. length
c. wave
d. type
Answer  Explanation 

ANSWER: length

Explanation:
No explanation is available for this question!


3)   Loud noise can

a. damage our ears
b. make us ill
c. disturb our sleep
d. interrupt conversation
Answer  Explanation 

ANSWER: damage our ears

Explanation:
No explanation is available for this question!


4)   We cannot hear alarm of a clock if there is

a. vacuum in the jar
b. air in the jar
c. liquid in the jar
d. solid in the jar
Answer  Explanation 

ANSWER: vacuum in the jar

Explanation:
No explanation is available for this question!


5)   The third effecter of sound created by vibrating strings is

a. angle of strings
b. thickness of strings
c. material of strings
d. height of strings
Answer  Explanation 

ANSWER: thickness of strings

Explanation:
No explanation is available for this question!


6)   Sound is made louder by increasing

a. wavelength
b. frequency
c. wave front
d. amplitude
Answer  Explanation 

ANSWER: amplitude

Explanation:
No explanation is available for this question!


7)   Trombone is also an example of

a. wind instrument
b. string instrument
c. soprano instrument
d. brass instrument
Answer  Explanation 

ANSWER: brass instrument

Explanation:
No explanation is available for this question!


8)   Sound is a form of

a. force
b. power
c. light
d. energy
Answer  Explanation 

ANSWER: energy

Explanation:
No explanation is available for this question!


9)   The loudness of sound is also known as

a. amplitude
b. wave front
c. volume
d. pace of sound
Answer  Explanation 

ANSWER: volume

Explanation:
No explanation is available for this question!


10)   The more dense the liquid, the

a. more slow the speed of sound
b. more fast the speed of sound
c. more distance covered by the sound
d. less distance covered by the sound
Answer  Explanation 

ANSWER: more fast the speed of sound

Explanation:
No explanation is available for this question!


11)   Singing and talking are the

a. artificial sounds
b. natural sounds
c. man-made sounds
d. sounds made electronically
Answer  Explanation 

ANSWER: man-made sounds

Explanation:
No explanation is available for this question!


12)   In large empty rooms, even a click keeps on

a. increasing
b. decreasing
c. repeating
d. coming
Answer  Explanation 

ANSWER: repeating

Explanation:
No explanation is available for this question!


13)   Sounds of thunder and horn of lorries are known as

a. loud sounds
b. soft sounds
c. high pitched sounds
d. low pitched sounds
Answer  Explanation 

ANSWER: loud sounds

Explanation:
No explanation is available for this question!


14)   Sound is created by our vocal cord due to

a. air in lungs
b. cilia in the throat
c. vibration in throat
d. vibration in lungs
Answer  Explanation 

ANSWER: vibration in throat

Explanation:
No explanation is available for this question!


15)   The normal value of decibel that our ears can detect is

a. -20
b. 0
c. 20
d. 40
Answer  Explanation 

ANSWER: 0

Explanation:
No explanation is available for this question!


16)   As compare to humans, bats can hear sounds only with

a. low frequency
b. low pitch
c. low amplitude
d. high pitch
Answer  Explanation 

ANSWER: high pitch

Explanation:
No explanation is available for this question!


17)   In one wavelength, wave passes through

a. one complete vibration
b. two complete vibrations
c. one and a half vibration
d. two and a half vibration
Answer  Explanation 

ANSWER: one complete vibration

Explanation:
No explanation is available for this question!


18)   If frequency is high, the peak of the waves would be

a. uneven
b. closer
c. distant
d. even
Answer  Explanation 

ANSWER: closer

Explanation:
No explanation is available for this question!


19)   If frequency increases,

a. wavelength also increases
b. amplitude also increases
c. number of waves also increases
d. amplitude decreases
Answer  Explanation 

ANSWER: number of waves also increases

Explanation:
No explanation is available for this question!


20)   The organs of a human that detect sounds are

a. eyes
b. ears
c. feet
d. hands
Answer  Explanation 

ANSWER: ears

Explanation:
No explanation is available for this question!