☰
GkSeries.com

NCERT Solutions for class 11 Physics | Chapter 15 - Waves

Free download in PDF Class 11 Physics Chapter 15 Wave Multiple Choice Questions and Answers for Board, JEE, NEET, AIIMS, JIPMER, IIT-JEE, AIEE and other competitive exams. MCQ Questions for Class 11 Physics with Answers were prepared based on the latest exam pattern. These short solved questions or quizzes are provided by Gkseries. These will help the students for preparation of their examination./p>

Go To Download Page
(1) A transverse harmonic wave on a string is described by y (x,t ) = 3.0 sin (36t + 0.018x + π/4) where x and y are in cm and t is in s. The positive direction of x is from left to right.
[A] The wave is travelling from right to left.
[B] The speed of the wave is 20 m/s.
[C] Frequency of the wave is 5.7 Hz.
[D] The least distance between two successive crests in the wave is 2.5 cm.
Answer: A, B, C
(2) A train whistling at constant frequency is moving towards a station at a constant speed V. The train goes past a stationary observer on the station. The frequency n′ of the sound as heard by the observer is plotted as a function of time t (Fig. in below) . Identify the expected curve.

Waves

[A] (a)
[B] (b)
[C] (c)
[D] (d)
Answer: (c)
(3) A string of mass 2.5 kg is under a tension of 200 N. The length of the stretched string is 20.0 m. If the transverse jerk is struck at one end of the string, the disturbance will reach the other end in
[A] one second
[B] 0.5 second
[C] 2 seconds
[D] data given is insufficient
Answer: 0.5 second
(4) A sound wave is passing through air column in the form of compression and rarefaction. In consecutive compressions and rarefactions,
[A] density remains constant.
[B] Boyle’s law is obeyed.
[C] bulk modulus of air oscillates.
[D] there is no transfer of heat.
Answer: there is no transfer of heat.
(5) Which of the following statements are true for wave motion?
[A] Mechanical transverse waves can propagate through all mediums.
[B] Longitudinal waves can propagate through solids only.
[C] Mechanical transverse waves can propagate through solids only.
[D] Longitudinal waves can propagate through vacuum.
Answer: Mechanical transverse waves can propagate through solids only.
(6) With propagation of longitudinal waves through a medium, the quantity transmitted is
[A] matter.
[B] energy.
[C] energy and matter.
[D] energy, matter and momentum.
Answer: energy.
(7) Change in temperature of the medium changes
[A] frequency of sound waves.
[B] amplitude of sound waves.
[C] wavelength of sound waves.
[D] loudness of sound waves.
Answer: wavelength of sound waves.
(8) Water waves produced by a motor boat sailing in water are
[A] neither longitudinal nor transverse.
[B] both longitudinal and transverse.
[C] only longitudinal.
[D] only transverse.
Answer: both longitudinal and transverse.
(9) The velocity of sound is maximum in
[A] Water
[B] Air
[C] Vacuum
[D] Metal
Answer: Metal
(10) The extension in a string , obeying Hookes law is X . The speed of sound in the stretched string is V . If the extension in the string is increased to 1.5 X , the speed of sound will be
[A] 1.22 V
[B] 0.61 V
[C] 1.50 V
[D] 0.75 V
Answer: 1.22 V
(11) The equation of wave traveling along string is y = 3 cos p (100t - x) in C.G.S. unit then wavelength is
[A] 1 m
[B] 2 cm
[C] 5 cm
[D] None of above
Answer: 2 cm
(12) 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
Answer: The tension in the string increases
(13) If the phase difference between two points is 60o on a wave velocity of 360 m/s and frequency 500 Hz , then path difference between the two points is
[A] 1 cm
[B] 6 cm
[C] 12 cm
[D] 24 cm
Answer: 12 cm
(14) A simple harmonic wave having amplitude A and time period T is represented by the equation y = 5 sin p(t + 4) metres. Then the value of A (in metres) and T (in seconds) are
[A] A = 5, T = 2
[B] A = 10, T = 1
[C] A = 5, T = 1
[D] = 10, T = 2
Answer: A = 5, T = 2
(15) Which of the following expressions is that of a simple harmonic progressive wave
[A] a sin wt
[B] a sin (wt) cos (kx)
[C] a sin (wt - kx)
[D] a cos kx
Answer: a sin (wt - kx)
(16) A tuning fork of frequency 480 Hz is in unison with pipe closed at one end vibrating in its first overtone. Then fundamental frequency of the pipe is
[A] 150 Hz
[B] 160 Hz
[C] 480 Hz
[D] 190 Hz
Answer: 480 Hz
(17) In stationary waves
[A] Energy is uniformly distributed
[B] Energy is minimum at nodes and maximum at antinodes
[C] Energy is maximum at nodes and minimum at antinodes
[D] None of these
Answer: Energy is minimum at nodes and maximum at antinodes
(18) Ultrasonic waves are those waves
[A] To which man can hear
[B] Man can not hear
[C] Are of high velocity
[D] Of high amplitude
Answer: Man can not hear
(19) A resonance air column of length 40 cm resonates with a tuning fork of frequency 450 Hz . Lgnoring 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
Answer: 720 m/s
(20) Two closed pipe produces 10 beats per second when emitting their fundamental nodes. If their lengths are in the ratio of 25: 26 their fundamental frequency in Hz are
[A] 270, 280
[B] 260, 270
[C] 260, 250
[D] 240, 250
Answer: 260, 250

Chapters

Click Here to Read more questions