Oscillations CBSE Questions & Answers

Oscillations

This is Physics Class 11 Oscillations CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
The angular velocities of three bodies in simple harmonic motion are\({{\rm{\omega }}_1}\), \({{\rm{\omega }}_2}\), \({{\rm{\omega }}_3}\) with the respective amplitudes as \({A_1}\) \({A_2}\) \({A_3}\) If all the three bodies have same mass and velocity,then
  • A
    \({{\rm{A}}_{\rm{1}}}{\omega ^{\rm{2}}}_{\rm{1}}\) = \({{\rm{A}}^{\rm{2}}}_{\rm{2}}{\omega ^{\rm{2}}}_{{\rm{2}} = }{{\rm{A}}^{\rm{2}}}_{\rm{3}}{\omega ^{\rm{2}}}_{\rm{3}}\)
  • B
    \({{\rm{A}}^{\rm{2}}}_{\rm{1}}{\omega _{\rm{1}}}\) = \({{\rm{A}}^{\rm{2}}}_{\rm{2}}{\omega _{{\rm{2}} = }}{{\rm{A}}^{\rm{2}}}_{\rm{3}}{\omega _{\rm{3}}}\)
  • C
    \({{\rm{A}}_{\rm{1}}}{\omega _{\rm{1}}}\) = \({{\rm{A}}_{\rm{2}}}{\omega _{{\rm{2}} = }}{{\rm{A}}_{\rm{3}}}{\omega _{\rm{3}}}\)
  • D
    \({{\rm{A}}^{\rm{2}}}_{\rm{1}}{\omega ^{\rm{2}}}_{\rm{1}}\) = \({{\rm{A}}^{\rm{2}}}_{\rm{2}}{\omega ^{\rm{2}}}_{{\rm{2}} = }{{\rm{A}}^{\rm{2}}}_{\rm{3}}{\omega ^{\rm{2}}}_{\rm{3}}\)
    Correct
2
The kinetic energy of a body executing S.H.M. is 1/3 of the potential energy. Then, the displacement of the body is x percent of the amplitude, where x is
  • A
    33.0
    Correct
  • B
    50
  • C
    87
  • D
    67
3
The total energy of a particle, executing simple harmonic motion is
  • A
    Independent of x
  • B
    \( \propto \); x
  • C
    \( \propto \); \({{\rm{x}}^{\rm{2}}}\)
  • D
    \( \propto \); \({\rm{x}}/{\rm{2}}\)
    Correct
4
A spring with spring constant k when stretched through 1 cm has a potential energy U. If it is stretched by 4 cm, the potential energy will become
  • A
    16U
  • B
    32U
    Correct
  • C
    4U
  • D
    8U
5
For a particle executing S.H.M having amplitude a, the speed of the particle is one-half of its maximum speed when its displacement from the mean position is
  • A
    2a
    Correct
  • B
    a/2
  • C
    \(\sqrt {3a} \)
  • D
    \(\sqrt {3a} \)/2
6
The period of a spring oscillating simple harmonically is
  • A
    T=2 \(\pi \) \(\sqrt {\left\{ {{K \over m}} \right\}} \)
  • B
    T=2 \(\pi \sqrt {\left\{ {{m \over K}} \right\}} \)
  • C
    T=2 \(\pi \sqrt {\left\{ {{{2m} \over K}} \right\}} \)
    Correct
  • D
    T=2 \(\pi \sqrt {\left\{ {{m \over {2K}}} \right\}} \)
7
A spring has a certain mass suspended from it and its period for vertical oscillations is \({{\rm{T}}_{\rm{1}}}\) . The spring is now cut into two equal halves and the same mass is suspended from one of the halves. The period of vertical oscillations is now \({{\rm{T}}_{\rm{2}}}\) .The ratio of \({{\rm{T}}_{\rm{1}}}\)/ \({{\rm{T}}_{\rm{2}}}\) is
  • A
    \({1 \over 2}\)
  • B
    \(\sqrt 2 \)
  • C
    2\(\sqrt 2 \)
  • D
    2.0
    Correct
8
A simple spring has length l and force constant K. It is cut into two springs of lengths \({{\rm{l}}_{\rm{1}}}\) and \({{\rm{l}}_{\rm{2}}}\) such that \({{\rm{l}}_{\rm{1}}}\) =n. \({{\rm{l}}_{\rm{2}}}\) (where n is an integer), the force constant of the spring of length \({{\rm{l}}_{\rm{2}}}\) is
  • A
    K/n (1+n)
  • B
    K (1 +n)
  • C
    K/(n +1)
    Correct
  • D
    K/(n +1)
9
In the arrangement shown in the figure, if the block of mass m is displaced, the frequency is given by
Question 9 figure 1
  • A
    n = (l/2 \(\pi \)) \(\sqrt {\left[ {({k_1} - {k_2})m} \right]} \)
    Correct
  • B
    (l/2 {/tex}\pi \() {tex}\sqrt {{{({k_1} - {k_2})} \over m}} \)
  • C
    n = (l/2 \(\pi \)) \(\sqrt {\left[ {({k_1} - {k_2})m} \right]} \)
  • D
    = (l/2 \(\pi \)) \(\sqrt {{{({k_1} - {k_2})} \over m}} \)
10
Two pendulums of length I meter and 16 meters start vibrating one behind the other from the same stand. At some instant the two are in the mean position in the same phase. The time period of shorter pendulum is T. The minimum time after which the two threads of the pendulums will be one behind the other is
  • A
    T/3
  • B
    T/4
  • C
    2T/5
    Correct
  • D
    4T/3
11
For all practical purposes, the motion of a simple pendulum is SHM,
  • A
    Only if the length of its string is at least one meter
  • B
    None of these
    Correct
  • C
    Only if the maximum angle which its string makes with the vertical is less than 342.
  • D
    Only if the maximum angle which the string makes with the vertical is less than I
12
A rubber ball with water, having a small hole in its bottom is used as the bob of a simple pendulum. The time-period of such a pendulum:
  • A
    Decreases with time
  • B
    Is a constant
  • C
    First increases and then decreases finally having same value as at the beginning
    Correct
  • D
    Increases with time
13
A mass M is suspended from a spring of negligible mass. The spring is pulled a little and then released so that the mass executes simple harmonic oscillations with a time period T.
  • A
    5/ 4
  • B
    41369.0
    Correct
  • C
    9/ 16
  • D
    25/ 16
14
The bob of a simple pendulum has a mass of 20 g. The period of oscillations of the pendulum is 0.75 s. When the mass of bob is increased to 40 g, without any other change, the time period now becomes
  • A
    1.5 s
  • B
    0.75 \(\sqrt 2 \)
  • C
    0.75 s
  • D
    0.75/ \(\sqrt 2 \)
    Correct
15
A pendulum suspended from a ceiling of a train has a period T when the train is at rest. When the train is accelerating with a uniform acceleration α, the period of oscillation will
  • A
    Remain unaffected
    Correct
  • B
    Increase
  • C
    Become infinite
  • D
    Decrease