MCQ Questions Chapter 12 Sound Class 9 Science

MCQ Class 9

Please refer to MCQ Questions Chapter 12 Sound Class 9 Science with answers provided below. These multiple-choice questions have been developed based on the latest NCERT book for Class 9 Science issued for the current academic year. We have provided MCQ Questions for Class 9 Science for all chapters on our website. Students should learn the objective based questions for Chapter 12 Sound in Class 9 Science provided below to get more marks in exams.

Chapter 12 Sound MCQ Questions

Please refer to the following Chapter 12 Sound MCQ Questions Class 9 Science with solutions for all important topics in the chapter.

MCQ Questions Answers for Chapter 12 Sound Class 9 Science

OBJECTIVE QUESTIONS

Question. The vibrations in the ear are amplified by
(a) hammer
(b) anvil
(c) stirrup
(d) all of these

Answer

D

Question. A marine survey ship emits a sound wave straight to the sea bed. It detects an echo 4.0 s later. Which is a possible depth of the sea?
(a) 600 m
(b) 1500 m
(c) 3000 m
(d) 10000 m

Answer

C

Question. Ultrasonic, infrasonic and audible waves travel through a medium with speeds Vu , Vi and Va respectively, then
(a) Vi = Va = Vu
(b) Vu > Va > Vi
(c) Vu < Va < Vi
(d) Va ≤ Va = Vu

Answer

A

Question. In case of longitudinal waves, the particles of medium vibrate
(a) in the direction of wave propagation
(b) opposite to the direction of wave propagation
(c) at right angles to the direction of wave propagation.
(d) none of the above

Answer

A

Question. Mechanical wave can travel
(a) in vacuum as well as in a medium
(b) in vacuum but not in a medium
(c) in a medium but not in vacuum
(d) neither in a medium nor in vacuum

Answer

C

Question. A big explosion on the moon cannot be heard on the earth because
(a) the explosion produces high frequency sound waves which are inaudible
(b) sound waves require a material medium for propagation
(c) sound waves are absorbed in the moon’s atmosphere
(d) sound waves are absorbed in the earth’s atmosphere

Answer

B

Question. Cochlea, basilar membrane and semicircular canals are the parts of
(a) outer ear
(b) middle ear
(c) inner ear
(d) all of these

Answer

C

Question. During night, distant sounds such as that of traffic and loudspeakers become louder. This is due to
(a) reflection of sound waves
(b) refraction of sound waves
(c) absence of other sounds
(d) clear perception of hearing

Answer

B

Question. An object moving at a speed greater than that of sound is said to be moving at
(a) ultrasonic speed
(b) sonic speed
(c) infrasonic speed
(d) supersonic speed

Answer

D

Question. If you go on increasing the stretching force on a wire in a guitar, its frequency
(a) increases
(b) decreases
(c) remains unchanged
(d) none of these

Answer

A

Question. An instrument commonly used in laboratory to produce a sound of some particular frequency is
(a) sonar
(b) electric bell
(c) tuning fork
(d) a stretched wire

Answer

C

Question. ………. is the vibrating part which enables us to speak.
(a) Vocal cords
(b) Larynx
(c) Ears
(d) Fingers

Answer

A

Question. The sound waves having a frequency more than 20,000 Hz are called
(a) infrasonic waves
(b) supersonic waves
(c) ultrasonic waves
(d) hypersonic waves

Answer

C

Question. Which of the following are applications of ultrasound?
1. To scan the womb of a pregnant lady.
2. To break up kidney stones and gall stones.
3. To detect flaws in metals.
(a) 1 and 2
(b) 2 and 3
(c) 1 and 3
(d) 1, 2 and 3

Answer

D

Question. A stretched slinky is given a sharp push along its length. A wave travels from one end to another. The wave so produced is
(a) transverse wave
(b) longitudinal wave
(c) stationary wave
(d) none of the above

Answer

B

Question. Two waves of sinusoidal waveforms are same wavelengths and different amplitude. They will be having
(a) same pitch and different intensity
(b) same quality and different intensity
(c) different quality and different intensity
(d) same quality and different pitch

Answer

A

Question. Of the following, the one which emits sound of higher pitch is
(a) mosquito
(b) man
(c) lion
(d) woman

Answer

A

Question. The membrane of a drum vibrates to produce sound. Similarly the string of a sitar vibrates to produce sound. Which part of a whistle vibrates to produce sound?
(a) Body of whistle
(b) Air column
(c) Mouth of the person
(d) All of these

Answer

B

Question. In the region of compression or rarefaction, in a longitudinal wave the physical quantity which does not change is
(a) pressure
(b) mass
(c) density
(d) volume

Answer

B

Question. Water waves are
(a) longitudinal
(b) transverse
(c) Both longitudinal and transverse
(d) neither longitudinal nor transverse

Answer

C

Question. An object moving at a speed greater than that of sound is said to be moving at
(a) ultrasonic speed
(b) sonic speed
(c) infrasonic speed
(d) supersonic speed

Answer

D

FILL IN THE BLANK

Question. Longitudinal waves cannot passed through _____

Answer

vacuum

Question. Sound waves having the frequency _____ are audible to human being.

Answer

500 cycles/second

Question. Velocity of sound in vacuum is _____

Answer

0

Question. The note of the lowest frequency in a musical reach is called ______

Answer

tone

Question. A transverse wave is made up of _____

Answer

crests an troughs

Question. The wavelength of a sound from a tuning fork of frequency 330 Hz is nearly _____ cm.

Answer

100

TRUE/FALSE

Question. Potential energy of simple harmonic oscillator at the mean position is always zero.

Answer

False

Question. The pitch of the sound as detected by the observer is independent of original frequency.

Answer

True

Question. Pitch of the voice of a child is higher than that of a boy.

Answer

True

Question. Longitudinal waves are produced in all the three states.

Answer

True

Question. Longitudinal waves consist of crests and troughs.

Answer

False

Question. A pure sine wave of sound is called melody.

Answer

False

MATCHING QUESTIONS

Question.

MCQ Questions Chapter 12 Sound Class 9 Science
Answer

P-3, Q-4, R-1, S-2

Question.

MCQ Questions Chapter 12 Sound Class 9 Science
Answer

P-3, Q-1, R-2, S-4

ASSERTION AND REASON

Question. Assertion : The flash of lightening is seen before the sound of thunder is heard.
Reason : Speed of sound is greater than speed of light.
Options:
(a) Both assertion and reason are true and reason is the correct explanation of assertion.
(b) Both assertion and reason are true but reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.

Answer

C

Question. Assertion : Echo is produced when sound is incident on hard and polished surface.
Reason : Sound energy can be totally reflected by objects with soft and loose texture.
Options:
(a) Both assertion and reason are true and reason is the correct explanation of assertion.
(b) Both assertion and reason are true but reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.

Answer

C

Question. Assertion : Two persons on the surface of moon cannot talk to each other.
Reason : There is no atmosphere on the moon.
Options:
(a) Both assertion and reason are true and reason is the correct explanation of assertion.
(b) Both assertion and reason are true but reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.

Answer

A

Question. Assertion : Waves produced by a motor boat sailing in water are both longitudinal and transverse in nature.
Reason : The longitudinal and transverse waves cannot be produced simultaneously.
Options:
(a) Both assertion and reason are true and reason is the correct explanation of assertion.
(b) Both assertion and reason are true but reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.

Answer

C

Question. Assertion : The velocity of sound increases with increase in humidity.
Reason : Velocity of sound does not depend upon the medium.
Options:
(a) Both assertion and reason are true and reason is the correct explanation of assertion.
(b) Both assertion and reason are true but reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.

Answer

C

Question. Assertion : The longitudinal waves are called pressure waves.
Reason : Propagation of longitudinal waves through a medium involves changes in pressure and volume of air, when compression and rarefaction are formed.
Options:
(a) Both assertion and reason are true and reason is the correct explanation of assertion.
(b) Both assertion and reason are true but reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.

Answer

A

Question. Assertion : Two persons on the surface of moon cannot talk to each other.
Reason : There is no atmosphere on moon.
Options:
(a) Both assertion and reason are true and reason is the correct explanation of assertion.
(b) Both assertion and reason are true but reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.

Answer

A

Question. Assertion : Transverse waves can be produced in liquids.
Reason : Light waves are transverse waves.
Options:
(a) Both assertion and reason are true and reason is the correct explanation of assertion.
(b) Both assertion and reason are true but reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.

Answer

B

Question. Assertion : Waves produced in a cylinder containing a liquid by moving its piston back and forth are longitudinal waves.
Reason : In longitudinal waves, the particles of the medium oscillate parallel to the direction of propagation of the wave.
Options:
(a) Both assertion and reason are true and reason is the correct explanation of assertion.
(b) Both assertion and reason are true but reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.

Answer

B

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