9th Class Science Sound Question Bank

Sound Summative Objective Problems Total Questions - 28

1)

Lucas wants to compare the loudness of two sound producing instruments. He uses a sound detector for this purpose. The test will be fair if

A)
both the instruments produce sounds of equal pitch

B)
both the instruments produce sounds of equal amplitudes

C)
the detector is placed at an equal distance from the two sources

D)
the distance between the detector and the sources changes continuously
View Solution

The approximate hearing ranges of some species are listed in the given table.
Species	Hearing range (Hz)
Human	20-20 000
Cat	45-60 000
Rabbit	360-40 000
Tuna	50-1 000
Ferret	16-45 000
Bullfrog	100-3 000

The frequency of the sound produced by a flute is 200 Hz. Which of the given species cannot hear this sound?

Cat

Tuna

Rabbit

Bullfrog

View Solution

3)

The hearing ranges of some animals are shown in the given bar graph.

Which of the given animals has the ability to hear sounds with the highest pitch?

A)
Grasshopper

B)
Human

C)
Bat

D)
Cat
View Solution
4)

The given table lists some characteristics of four sounds I, II, III, and IV.

Sound Amplitude (cm) Frequency

I 1 1

II 2 3

III 3 2

IV 4 2

Which sound has the highest pitch?

A)
I

B)
II

C)
III

D)
IV
View Solution
5)

Calculate the wavelength of a sound wave whose frequency is 220 Hz and speed is 440 m/s in a given medium.

A)
3 m

B)
5 m

C)
2 m

D)
4 m
View Solution
6)

A person is sitting 200 metres away from a 20 Hz sound source. What is the time interval at which successive compression pulses from the source reach him?

A)
0.5 s

B)
0.05 s

C)
0.005 s

D)
0.0005 s
View Solution
7)

A sound wave travelling in air has wavelength of\[1.6\times {{10}^{-2}}m.\]If the velocity of sound is 320m/s, calculate the frequency of sound.

A)
10,000 Hz

B)
20,000 Hz

C)
15,000 Hz

D)
25,000 Hz
View Solution
8)

If 25 second wave are produced per second, what is the frequency in hertz?

A)
25 Hertz

B)
50 Hertz

C)
15 Hertz

D)
75 Hertz
View Solution
9)

Sound waves travel with a speed of about 330 m/s. What is the wavelength of sound where frequency is 500 Hertz?

A)
0.6 m

B)
0.5 m

C)
0.8 m

D)
9 m
View Solution
10)

A circular disc with 1500 holes in rotating at 720 r.p.m. If a jet of are passes through the hole, the frequency of sound emitted is

A)
21600 hz

B)
2160 hz

C)
\[\frac{1}{2160\,hz}\]

D)
None
View Solution

11)

The given table lists some characteristics of four sounds I, II, III, and IV.
Sound	Amplitude (cm)	Frequency (Hz)
I	1	1
II	3	4
III	2	3
IV	2	4

Which two sounds have the same loudness?

I and II

I and III

II and IV

III and IV

View Solution

12)

Sound is produced by the vibration of an object. It travels through a medium such as air by forming alternate regions of compression and rarefaction of air molecules. As a sound travels through air, the regions of compression and rarefaction in it can be shown as

A)

B)

C)

D)

View Solution

13)

Matrix matching

(a) Hz	(p) Wavelength
(b) \[f\times \lambda \]	(q) frequency
(c) \[\lambda /T\]	(r) Velocity
(d) meter	(s) Amplitude

a-q; b-q; c-p; d-p

a-q; b-r, c-r, d-s

a-q; b-r; c-r; d-s

a-q; b-s; c-s; d-p

View Solution

14)

Statement A: Mechanical Transverse wave can travel through solids & at the surface of liquid only. Statement B: Mechanical Transverse wave can travel through solid, liquid & gases.

A)
Both the Statements are True and statement ?I? is correct explanation of Statement 'II'.

B)
Both the Statements are True and statement ?I? is not correct explanation of Statement 'II'

C)
Statement 'I' is True, Statement 'II' is False.

D)
Statement 'I' is False, Statement 'II' is true
View Solution
15)

Mechanical (elastic ) waves can travel in

A)
In a medium but not a vacuum

B)
In a vacuum as well as in a medium

C)
In a vacuum but not in medium

D)
neither in vacuum nor in a medium.
View Solution
16)

The given figure shows four similar sound waves entering four different media of equal thickness, t.

The sound wave will emerge first from medium

A)
I

B)
II

C)
III

D)
IV
View Solution
17)

When Owen strikes two tuning forks with a hammer they produce melodious sounds. He feels that the sound produced by fork I is louder than that produced by fork n. The sound wave produced by fork II is shown in the given figure.

Which figure shows the graphical representation of the sound produced by fork I?

A)

B)

C)

D)

View Solution
18)

Which of the following pairs of sound waves represents sounds of different levels of loudness?

A)

B)

C)

D)

View Solution
19)

Jim beats two empty drums. The sound waves produced by the drums are shown in the given figure.

From the graphical form of the sound waves it can be said that the produced sounds have different

A)
amplitudes

B)
intensities

C)
volumes

D)
pitches
View Solution
20)

An echo is heard after 0.8 s, when a person fires a cracker 132.8 m from a high building. What is the speed of sound?

A)
315 m/s

B)
332 m/s

C)
320 m/s

D)
310 m/s
View Solution
21)

A man stands in between two cliffs and explodes a cracker. He hears the first echo after 0.6s and the second echo after 2.4s. Calculate the distance between the cliffs, (speed of sound = 336 m/s)

A)
515 m

B)
520 m

C)
504 m

D)
505 m
View Solution
22)

A dog barks in a park and hears its echo after 0.5 second. If the sound of its bark got reflected by a nearby building, find the distance between the dog and the building. Take the speed of sound in air is 346 m/s.

A)
86.5 m

B)
86 m

C)
85 m

D)
75 m
View Solution
23)

A ship sends a signal and receives it back from the bottom of the sea after 6s. What is the depth of the sea at that place? (speed of sound in sea water is\[\text{145}0\text{ m}{{\text{s}}^{-\text{1}}}\])

A)
4.35 km

B)
3.35 km

C)
435 km

D)
335 km
View Solution
24)

Using the sonar, sound pulses are emitted at the surface, the pulses after being reflected from the bottom are detected, if the time interval from the emission to the detection of the sound pulses is 2 seconds, find the depth of the water. (Taking velocity of sound through water = 1531 m/s)

A)
1500 m

B)
1000 m

C)
1531 m

D)
1530 m
View Solution
25)

A sonar device on a submarine send out a signal and receives an echo 5 seconds later. Calculate the speed of sound in water, if the distance of the object from the submarine is 3625 m.

A)
1440 m/s

B)
1460 m/s

C)
1450 m/s

D)
1470 m/s
View Solution
26)

A person fires a gun in front of a building 167m away. If the speed of sound is 334 m/s. Calculate the time in which he hears an echo.

A)
0.2 s

B)
2 s

C)
1.0 s

D)
0.1 s
View Solution
27)

The distance between the observer (source of sound) and wall is 500 m. The observer hear the first echo after 2 sec then velocity of the sound is

A)
250 m/s

B)
500 m/s

C)
750 m/s

D)
1000 m/s
View Solution
28)

                A man stands in between two parallel cliffs and fires a gun. Hears two successive echos after 2 second and 4.5 seconds. What is the distance between the two cliffs.

A)
332 m

B)
1079 m

C)
482 m

D)
747 m
View Solution

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9th Class Science Sound Question Bank

done Sound Summative Objective Problems Total Questions - 28

Download Complete Course

Sound Summative Objective Problems Total Questions - 28