#### Acoustics English Medium Free Online Test 1 Mark Questions with Answer Key 2020 - 2021

10th Standard

Reg.No. :
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Science

Time : 00:20:00 Hrs
Total Marks : 20

Part A

10 x 1 = 10
1. Velocity of sound in a gaseous medium is 330 m s-1. If the pressure is increased by 4 times without causing a change in the temperature, the velocity of sound in the gas is

(a)

330 m s-1

(b)

660 m s-1

(c)

165 ms-1

(d)

990 ms-1

2. If a sound wave travels with a frequency of 1.25 x 104 Hz 344 ms-1, the wavelength will be

(a)

27.52 m

(b)

275.2 m

(c)

0.02752 m

(d)

2.752 m

3. Velocity of sound in the atmosphere of a planet is 500 m s-1. The minimum distance between the sources of sound and the obstacle to hear the echo, should be

(a)

17 m

(b)

20 m

(c)

25 m

(d)

50 m

4. The velocity of sound is affected by

(a)

temperature

(b)

density

(c)

pressure

(d)

all the above

5. The region of a sound wave having low pressure is

(a)

interference

(b)

refraction

(c)

rarefaction

(d)

compression

6. Distance between two consecutive compressions is

(a)

λ

(b)

λ/2

(c)

λ/4

(d)

7. The pitch of sound depends on

(a)

frequency

(b)

amplitude

(c)

both

(d)

none

8. Which voice is likely to have minute frequency?

(a)

baby girl

(b)

boy

(c)

A man

(d)

A woman

9. Sound propagates maximum in

(a)

gas

(b)

liquid

(c)

solid

(d)

all

10. A source emits a frequency of 1 kHz is moving toward a rest listener with a speed of 0.9 V, where V is the speed of sound wave. The frequency heard by the listener is ________.

(a)

10 Hz

(b)

0.1 Hz

(c)

100 Hz

(d)

10 kHz