Work Sheet MCQs 1. Sound is produced from the ------------- bodies. a) Vibrating b) m...
Work Sheet
MCQs
1. Sound is produced from the ------------- bodies.
a) Vibrating
b) moving c)
rotating
2. Sound waves are produced in --------------
a) Vacuum b)
space c) air
3. Sound waves are of ------------ nature
a) Transverse b)
longitudinal c) SHM
4. If area of sounding body is decreased then sound is------------
a) Decreased b)
increased c) remains
same
5. The are of vibrating body is increased then sound is __________-
a) Increased b)
decreased c) remains
same
6. To distinguish between faint and loud sounds we use__________--
a) Pitch b)
Loudness c) quality
7. If we need to distinguish between two sounds of same loudness
and pitch we use__________
a) Quality b)
loudness c) pitch
8. Unit of intensity is
a) Wm2 b)
Wm1 c)
Wm-2
9. Intensity level is given by __Wm-2.
a) L-I b)
L-L0 c)
I-I0
10. The least intensity that a human can hear is
a) 10-10 b)
10-12 c)
10-14
11. Zero bell is equal to
a) 10-10Wm-2 b)
10-12Wm-2 c)
10-14Wm-2
12. Reflection is also called_______
a) Echo b)
refraction c)
interference
13. The speed of sound in air is ________
a) 380ms-1 b)
480ms-1 c)
343ms-1
14. Speed of sound is greater in________
a) Solids b)
liquids c)
gases
15. The range of human air to hear the sound
a) 200-20000 b)
20-20000 c)
20-2000
16. Bats can hear frequencies up to
a) 120000 b
) 100000 c)
10000
17. Cats can hear frequencies up to
a) 20000 b)
25000 c)
35000
18. Sound waves travels from its source to your ear by
a) Change in air pressure b)
vibrations in wires c) infrared
19. The loudness of sound is most closely related to its
a) Frequency b)
period c)
amplitude
20. Which form of energy is sound?
a) Mechanical b)
electrical c)
thermal
Short Questions:
1. What is the necessary condition for the production of sound?
2. What is the effect of area of sounding body?
3. What is pitch?
4. What is the nature of sound waves?
5. Do sound waves move in vacuum?
6. Write the formula to find the speed of sound.
7. Do sound waves need any material medium for their propagation?
8. What do you understand by loudness of sound?
9. What is quality of sound?
10. What is intensity of sound write its formula?
11. What is meant by echo?
12. What is the difference between noise and music?
13. What is Ultrasound?
14. Write any 2 uses of ultrasound.
Long Questions:
1. If in Anarkali Bazaar Lahore, intensity level of sound is 80 dB,
what will be the intensity of sound there?
2. A ship sends out ultrasound that returns from the seabed and is
detected after 3.42s. If the speed of ultrasound through seawaters 1531ms-1,
what is the distance of the seabed from the ship?
3. A sound wave has a frequency of 2 kHz and wavelength 35cm. How
long will it take to travel 1.5 km?
4. A normal conversation involves sound intensities of about 3.0×10-6
W m-2. What is the decibel level for this intensity? What is the
intensity of the sound for 100 dB?
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