NCERT Class 11 Chapter 15 Physics Waves MCQ

NCERT Class 11 Chapter 15 Physics Waves MCQ | Questions & Answers: Curious to learn more about the Waves concept in NCERT Class 11 Physics Chapter 15? If yes, then do attempt the MCQ Online Quiz that we have accommodated here exclusively for you guys. This article allows you to learn where you stood with regard to your knowledge about the Waves topic. So, attempt the quiz as many times as you want till you wish to perfect yourselves.

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1. When a sound wave goes from one medium to another, the quantity that remains unchanged is

A. frequency

B. wavelength

C. amplitude

D. speed

2. For which of the following do the longitudinal waves exist?

A. Both

B. Air

C. Water

D. None of these

3. Sound travels in rocks in the form of

A. both longitudinal and transverse elastic waves

B. non-elastic waves

C. transverse elastic waves only

D. longitudinal elastic waves only

4. From a point source, if amplitude of waves at a distance r is A, its amplitude at a distance 2r will be

A. A/2

B. A/4

C. 2 A

D. A

5. The property of a medium necessary for wave propagation is

A. All of the above

B. Elasticity

C. Inertia

D. Low resistance

6. The ratio of the speed of a body to the speed of sound is called

A. Mach number

B. Sonic index

C. Doppler ratio

D. Refractive index

7. Sound waves transfer

A. both energy and momentum

B. only energy not momentum

C. momentum

D. energy

8. The reason for introducing Laplace correction in the expression for the velocity of sound in a gaseous medium is

A. no change in the heat of the medium during the propagation of the sound through it

B. no change in the temperature of the medium during the propagation of the sound through it

C. change in the pressure of the gas due to the compression and rarefaction

D. change in the volume of the gas

9. Which of the following changes at an antinode in a stationary wave?

A. Neither pressure nor density

B. Both pressure and density

C. Pressure only

D. Density only

10. What is the effect of humidity on sound waves when humidity increases?

A. Speed of sound waves is more

B. Speed of sound waves is less

C. Speed of sound waves remains same

D. Speed of sound waves becomes zero

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11. Which of the following statements is/are correct about the standing wave?
I. In a standing wave the disturbance produce is confined to the region where it is produced.
II. In a standing wave, all the particles cross their mean position together.
III. In a standing wave, energy is transmitted from one region of space to other

A. I and II

B. Only II

C. Only III

D. I, II and III

12. The rate of transfer of energy in a wave depends

A. directly on the square of the wave amplitude and square of the wave frequency

B. directly on the square of the wave amplitude and root of the wave frequency

C. directly on the wave amplitude and square of the wave frequency

D. None of these

13. If vibrations of a string are to be increased by a factor of two, then tension in the string must be made

A. twice

B. eight times

C. half

D. four times

14. The fundamental frequency of a closed end organ pipe is n. Its length is doubled and radius is halved. Its frequency will become nearly

A. n/2

B. n/3

C. n

D. 2 n

15. The fundamental frequency of an organ pipe is 512 Hz. If its length is increased, then frequency will

A. decrease

B. increase

C. remains same

D. cannot be predicted

16. What is the effect of increase in temperature on the frequency of sound produced by an organ pipe?

A. increases

B. no effect

C. decreases

D. erratic change

17. Frequencies of sound produced from an organ pipe open at both ends are

A. even and odd harmonics

B. only odd harmonics

C. only even harmonics

D. only fundamental note

18. closed organ pipe (closed at one end) is excited to support the third overtone. It is found that air in the pipe has

A. four nodes and four antinodes

B. four nodes and three antinodes

C. three nodes and four antinodes

D. three nodes and three antinodes

19. If there are six loops for 1 m length in transverse mode of Melde’s experiment., the no. of loops in longitudinal mode under otherwise identical conditions would be

A. 3

B. 6

C. 12

D. 8

20. The fundamental frequency of a closed organ pipe of length 20 cm is equal to the second overtone of an organ pipe open at both the ends. The length of organ pipe open at both theends is

A. 120 cm

B. 140 cm

C. 80 cm

D. 100 cm

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21. A resonance air column of length 40 cm resonates with a tuning fork of frequency 450 Hz. Ignoring end correction, the velocity of sound in air will be

A. 720 m/s

B. 820 m/s

C. 920 m/s

D. 1020 m/s

22. An observer is moving towards a stationary source of frequency 250 Hz with a velocity of 40 m/s. If the velocity of sound is 330 m/s, the apparent frequency heard by the observer will be

A. 320 Hz

B. 300 Hz

C. 280 Hz

D. 260 Hz

23. With the increase in temperature, the frequency of the sound from an organ pipe

A. Decreases

B. Increases

C. Remain unchanged

D. Changes erratically

24. Loudness of a note of sound is

A. Directly proportional to amplitude of the wave

B. Directly proportional to square of amplitude of wave

C. Directly proportional to velocity of the wave

D. Directly proportional to square of velocity of the wave

25. The frequency of the note produced by plucking a given string increases as

A. The length of the string increases

B. The tension in the string increases

C. The tension in the string decreases

D. The mass per unit length of the string increases