CBSE Class 8 Science Worksheet
Sound
1.
State True or False: A short flute will produce sound of lower pitch than a long flute.
A)
true
B)
false
2.
Choose the correct option: Unit of time period of oscillation is __________.
A)
second
B)
Hertz
C)
Watt
D)
Volt
3.
State True or False: Sound can't travel through solid.
A)
true
B)
false
4.
Fill in the blanks: The unit which is used to measure the loudness of sound is ______________.
5.
State True or False: Shriller sound has more frequency.
A)
true
B)
false
6.
Choose the correct option: The speed of sound is maximum in __________.
A)
air
B)
metals
C)
water
D)
Vacuum
7.
Choose the correct option: Vibrations in a body produces ________.
A)
light
B)
pressure
C)
force
D)
sound
8.
State True or False: Speed of light is very high as compared to that of sound.
A)
true
B)
false
9.
Fill in the blanks: Higher the amplitude of vibration, ____________ is the pitch.
10.
Fill in the blanks: The average rate of oscillations of a simple pendulum is 200 oscillations per seconds. Its time period in milliseconds is ____________.
11.
Which of the following frequency of sound is heard by dogs not humans?
A)
2.7kHz
B)
15kHz
C)
320Hz
D)
22kHz
12.
Choose the correct option: 2 Hz is _________.
A)
1 vibration per minute
B)
120 vibrations per minute
C)
60 vibrations per second
D)
1 vibration per hour
13.
State True or False: When amplitude of vibration is large, the sound produced is loud.
A)
true
B)
false
14.
Choose the correct option: The maximum displacement of a vibrating body from its mean position is known as ___________.
A)
frequency
B)
pitch
C)
amplitude
D)
time period
15.
What magnitude of noise can be physically harmful?
A)
30dB
B)
50dB
C)
90dB
D)
40dB
16.
State True or False: Noise pollution may cause partial hearing impairment.
A)
true
B)
false
17.
Choose the correct option: The normal range of vocal cord in female is _________.
A)
20mm
B)
15mm
C)
40mm
D)
10mm
18.
Why the voices of men, women and children are different ?
19.
Fill in the blanks: Bat uses ______________ sound to catch its preys.
20.
State True or False: Speed of sound is more in air than in water.
A)
true
B)
false
CBSE Class 8 Science Worksheet
Sound
Answers
1.
Option A
2.
Option A
3.
Option B
4.
decibel
5.
Option A
6.
Option B
7.
Option D
8.
Option A
9.
higher
10.
5
11.
Option D
12.
Option B
13.
Option A
14.
Option C
15.
Option C
16.
Option A
17.
Option B
18.
because vocal cords in men are about 20mm long. In women these are about 5mm shorter. Children have very short vocal cords.
19.
ultrasonic
20.
Option B
