HOTS Questions: Sound - Class 9 MCQ

# HOTS Questions: Sound - Class 9 MCQ

Test Description

## 25 Questions MCQ Test Science Class 9 - HOTS Questions: Sound

HOTS Questions: Sound for Class 9 2024 is part of Science Class 9 preparation. The HOTS Questions: Sound questions and answers have been prepared according to the Class 9 exam syllabus.The HOTS Questions: Sound MCQs are made for Class 9 2024 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests for HOTS Questions: Sound below.
Solutions of HOTS Questions: Sound questions in English are available as part of our Science Class 9 for Class 9 & HOTS Questions: Sound solutions in Hindi for Science Class 9 course. Download more important topics, notes, lectures and mock test series for Class 9 Exam by signing up for free. Attempt HOTS Questions: Sound | 25 questions in 25 minutes | Mock test for Class 9 preparation | Free important questions MCQ to study Science Class 9 for Class 9 Exam | Download free PDF with solutions
 1 Crore+ students have signed up on EduRev. Have you?
HOTS Questions: Sound - Question 1

### The crest and trough are the parts of ____ wave.

Detailed Solution for HOTS Questions: Sound - Question 1

The upward movement from mean position is called crest and downward movement is called troughs. The crest and trough are the parts of a transverse wave. The wavelength of the wave is a combination of the crest and trough.

HOTS Questions: Sound - Question 2

### Statement A: Speed of sound is same at different temperature  Statement B: Loudness is measured in decibels.  Which of the two statements is true?

Detailed Solution for HOTS Questions: Sound - Question 2

Speed of sound is different at different temperature. with increase in temperature, speed of sound increases. Loudness of sound is measured in decibels.

HOTS Questions: Sound - Question 3

### Match the following with correct response.

Detailed Solution for HOTS Questions: Sound - Question 3

Speed of sound in aluminum = 6420 m /s
Speed of sound in water = 1520 m /s
Speed of sound in air at 25° C = 347 m/s
Speed of sound in oxygen gas = 328 m/s

HOTS Questions: Sound - Question 4

Principle of reflection of sound is used in

Detailed Solution for HOTS Questions: Sound - Question 4

The principle of reflection of sound is used in megaphone, sound boards and stethoscope and other instruments.

HOTS Questions: Sound - Question 5

X – rays, light rays are electromagnetic waves is a

Detailed Solution for HOTS Questions: Sound - Question 5

X-rays, light rays are electrostatic waves. These waves do not require material medium for its propagation.

HOTS Questions: Sound - Question 6

Frequency of infrasonic waves is ____________ than frequency of ultrasound waves.

Detailed Solution for HOTS Questions: Sound - Question 6

Frequency of infrasonic waves is less than frequency of ultrasound waves. Frequency of infrasonic waves are less than 20Hz and frequency of ultrasonic waves are greater than 20,000Hz.

HOTS Questions: Sound - Question 7

“Due to the high power of ultrasound waves. It is used for breaking and cutting objects” The above statement is

Detailed Solution for HOTS Questions: Sound - Question 7

Ultrasound waves vibrate at frequency higher than 20,000Hz. Vibration at such a high speed can be used to breaking and cutting objects like stone in kidney.

HOTS Questions: Sound - Question 8

Match the following with correct response.

Detailed Solution for HOTS Questions: Sound - Question 8

The correct option is B.

Echo -  the repetition of a sound caused by reflection of sound waves.

A reverberation, or reverb, is created when a sound or signal is reflected causing numerous reflections to build up and then decay as the sound is absorbed by the surfaces of objects in the space – which could include furniture, people, and air.

Sonar is a technique that uses sound propagation to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels.

The concave surface of the sound board reflects the sound waves of the speaker towards the audience and hence prevents the spreading of sound in various directions. Due to this, sound is distributed uniformly throughout the hall and even the persons sitting at the back of the hall can hear the speech easily.

HOTS Questions: Sound - Question 9

Sound wave is a

Detailed Solution for HOTS Questions: Sound - Question 9

Sound wave propagates as compressions & rarefactions in the medium. Sound waves are longitudinal waves.

HOTS Questions: Sound - Question 10

The upper limit of frequency of sound waves audible to human beings are

Detailed Solution for HOTS Questions: Sound - Question 10

The range of hearing of normal human being is form 20 Hz to 20,000Hz. This range is called as audible range of human beings.
upper limit means the higher value

HOTS Questions: Sound - Question 11

Statement A: Human beings are ultrasound deaf
Statement B: Ultrasonic waves can travel easily in solid, liquid and gases.
Which of the two statements is true?

Detailed Solution for HOTS Questions: Sound - Question 11

Human beings are ultrasound deaf as human are not able to hear frequency of sound above 20,000Hz. Ultrasonic waves can travel in solid, liquid and gas but reflect backs in presence of obstruction.

HOTS Questions: Sound - Question 12

Match the following with correct response.

HOTS Questions: Sound - Question 13

The maximum displacement of the particle of the mean from its mean position is called the

Detailed Solution for HOTS Questions: Sound - Question 13

The maximum displacement from the particle of the mean position is called the Amplitude. Loudness of sound depends upon amplitude.

HOTS Questions: Sound - Question 14

The distance between a consecutive crest and trough is x. The wavelength of the wave is

Detailed Solution for HOTS Questions: Sound - Question 14

The wavelength is the distance between two consecutive crest or trough in case of transverse wave. Here, distance between consecutive crest and trough is x, so, wavelength will be 2x.

HOTS Questions: Sound - Question 15

Match the following with correct response.

HOTS Questions: Sound - Question 16

An echo is heard when-
A. Minimum distance is 17m
B. Minimum time gap between two sounds is 1/10th of second
C. Minimum distance is 18m
D. Minimum time gap between two sounds is 1/100th of second

Detailed Solution for HOTS Questions: Sound - Question 16

Two conditions for echo to be heard are as follows:-

1. 17 m minimum distance should be there.
2. Persistence of hearing is 0.1 secor minimum time gap between two sounds is 1/10 second.

HOTS Questions: Sound - Question 17

Which wave property determines loudness?

Detailed Solution for HOTS Questions: Sound - Question 17

Loudness of sound depends upon amplitude. Amplitude is the maximum displacement from mean position.

HOTS Questions: Sound - Question 18

Children can hear sound of frequency up to

Detailed Solution for HOTS Questions: Sound - Question 18

Children can hear sound of frequency up to 25,000Hz which is more than normal adult hearing range.

HOTS Questions: Sound - Question 19

Ultra sound is produced by
A. Tortoise
B. Bats
C. Dolphins
D. Dogs

Detailed Solution for HOTS Questions: Sound - Question 19

The correct option is D.
Animals such as bats,tortoises, dogs  and dolphins send out ultrasound waves and use their echoes, or reflected waves, to identify the locations of objects they cannot see. This is called echolocation. Animals use echolocation to find prey and avoid running into objects in the dark.

HOTS Questions: Sound - Question 20

The eardrum is a

Detailed Solution for HOTS Questions: Sound - Question 20

The eardrum is a stretched membranous structure at the junction of outer ear and middle ear. Vibration of eardrum causes production of sound that we hear.

HOTS Questions: Sound - Question 21

A source produces 20 crests and 20 troughs in 0.2 second. Find the frequency of the wave.

Detailed Solution for HOTS Questions: Sound - Question 21

There are 20 crests and 20 trough in 0.2s, which implies 20 waves.

And if there are 20 crests and 20 trough, this mean that there are 20 waves in 0.2s

∴ Frequency= Number of waves/ Time taken

=20/0.2=200/2 = 100Hz

∴ν = 100Hz

Option (C) is the correct answer.

HOTS Questions: Sound - Question 22

A wave moves a distance of 10m in 0.05 second. Find the wavelength of the wave if frequency is 200Hz?

Detailed Solution for HOTS Questions: Sound - Question 22

Speed = distance/time, 10m/0.05s = 200m/s. wavelength = wave speed / frequency = 200 ms−1/200Hz = 1m.

HOTS Questions: Sound - Question 23

A bat hears the echo of its squeak after 0.1 second. How far is the obstacle from the bat? Speed of sound is 344 m/s.

Detailed Solution for HOTS Questions: Sound - Question 23

Speed of sound = 344m/s. time taken to hear echo = 0.1s. 2×distance0.1s. 2×distance = speed×time. 2×d =344×0.1 = 34.4 m. d = 17.2m.

HOTS Questions: Sound - Question 24

Cochlea, semicircular canals and the auditory nerve are associated with

Detailed Solution for HOTS Questions: Sound - Question 24

Cochlea, semicircular canals and auditory nerve are associated with inner ear.

HOTS Questions: Sound - Question 25

“Wave motion shifts mass from one region to another” The above statement is

Detailed Solution for HOTS Questions: Sound - Question 25

Wave motion shifts wave energy from one region to another region. Mass is not transferred during wave motion.

## Science Class 9

80 videos|352 docs|97 tests
Information about HOTS Questions: Sound Page
In this test you can find the Exam questions for HOTS Questions: Sound solved & explained in the simplest way possible. Besides giving Questions and answers for HOTS Questions: Sound , EduRev gives you an ample number of Online tests for practice

## Science Class 9

80 videos|352 docs|97 tests