Sound Physics Test 02

Total Questions: 21

1 - The speed of sound in air at 100°C is:

A ) 380ms-¹
B ) 382ms-¹
C ) 386ms-¹ ✅
D ) 300ms-¹

2 - The intensity level of whispering is:

A ) 20dB
B ) 30dB ✅
C ) 40dB
D ) 50dB

3 - The intensity of rustling of leaves is:

A ) 10-¹¹ Wm-² ✅
B ) 10-¹⁰ Wm-²
C ) 10-⁹ Wm-²
D ) 10 Wm-²

4 - Which frequency is used by elephants to communicate with each other?

A ) Zero frequency
B ) low frequency ✅
C ) medium frequency
D ) high frequency

5 - The intensity level of train siren is:

A ) 150dB
B ) 130dB
C ) 100dB
D ) 120dB ✅

6 - The pitch of a sound is most closely related to its:

A ) frequency ✅
B ) period
C ) wavelength
D ) amplitude

7 - The quality of sound is most closely related to its:

A ) wave from ✅
B ) period
C ) amplitude
D ) frequency

8 - Safe level of noise depends on factors:

A ) one
B ) two ✅
C ) three
D ) four

9 - The technique or method used to absorb undesirable sounds by soft and porous surface is called:

A ) ultrasonics
B ) acoustic protection ✅
C ) infrasonics
D ) echo

10 - Mice can hear frequencies upto:

A ) 100,000 Hz ✅
B ) 25,000 Hz
C ) 120,000 Hz
D ) 1,000Hz

11 - Sound waves having frequency higher than 20,000 Hz are called:

A ) ultrasonic ✅
B ) infrasonic
C ) audible
D ) echo

12 - 1 bel =

A ) 0.1 dB
B ) 10 dB ✅
C ) 100 dB
D ) 0.01 dB

13 - Ultrasound waves carry energy:

A ) less
B ) more ✅
C ) equal
D ) none of these

14 - Level of noise recommended in eight-hour work day:

A ) 80-90 dB
B ) 80-85 dB
C ) 80-90 dB ✅
D ) 90-95 dB

15 - The sensation of sound persists in our brain for:

A ) 0.1 sec ✅
B ) 0.01 sec
C ) 1 sec
D ) 10 sec

16 - The speed of sound in a liquid is ____ than that in gases:

A ) ten times
B ) fifteen times
C ) five times ✅
D ) two times

19 - Example of Mechanical waves is:

A ) radio waves
B ) X-rays
C ) light wavse
D ) sound waves ✅

20 - The main categories of waves are:

A ) 1
B ) 2 ✅
C ) 3
D ) 4

21 - Sound waves frequency lower than 20Hz are called:

A ) ultrasonic
B ) infrasonic ✅
C ) audible
D ) echo