Tag: oscillations

Quizzes (16) Questions (206)

Questions Related to oscillations

Multiple choice resonance oscillations physics

Equations y = 2A cos$^{2}$ $\omega $t and y = A (sin $\omega $  + $\sqrt{3}$ cos $\omega $t  ) represent the motion of two particles.

  1. Only one of these is S.H.M.

  2. Ratio of maximum speeds is 2 : 1

  3. Ratio of maximum speeds is 1 : 1

  4. Ratio of maximum accelerations is 1 : 4
Reveal answer Fill a bubble to check yourself
C Correct answer
Multiple choice resonance oscillations physics

Your friend is playing a song on a piano. Whenever your friend hits a certain key, the lamp on top of the piano rattles. Explain why the lamp rattles.

  1. The lamp rattles because of the occurring of interference

  2. The lamp rattles because of the occurring of diffraction

  3. The lamp rattles because of the occurring of resonance

  4. None of the above

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This happens due to resonance (A phenomenon in which a vibrating system or external force drives another system to oscillate with a greater amplitude at a specific frequency). The lamp on top of the piano has a resonant frequency equal to one of the notes being played.

Multiple choice resonance oscillations physics

During resonance, sound waves tend to absorb

  1. more energy

  2. less energy

  3. no energy

  4. infinite energy
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

System to absorb more energy when the frequency of its oscillations matches the system's natural frequency of vibration than it does at other frequencies.

Multiple choice resonance oscillations physics

A glass tube of $1.0 m$ length is filled with water. The water can be drained out slowly at bottom of the tube. If a vibrating turning fork of frequency $500 Hz$ is brought at the upper end of the tube and the velocity of sound is $330 \,\,m\,\,s^{-1}$, then the total number of resonances obtained will be:

  1. 4

  2. 3

  3. 2

  4. 1
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Wavelength of the sound produced is,
$\lambda = \dfrac{Velocity}{Frequency} $


$= \dfrac{330\,\,m\,\,s^{-1}}{500\,\,s^{-1}} = 0.66\,\,m$
The resonance occurs at
$\dfrac{\lambda}{4},\dfrac{3\lambda}{4},\dfrac{5\lambda}{4},\dfrac{7\lambda}{4},.....$
i.e., at $0.165\,\,m, 0.495\,\,m, 0.825\,\,m, 1.155\,\,m$. As the length of the tube is only $1.0\,\,m$, hence $3$ resonance will be observed.

Multiple choice free, damped and forced oscillations free, forced and damped oscillations oscillations oscillation and waves physics

$mx^{2} - bx + k = 0$. Find time after which to the energy will become half of initial maximum value in damped forced oscillation.

  1. $t = \dfrac {m}{b} + \dfrac {1}{2} ln2$
  2. $t = \dfrac {m}{b} \times \dfrac {2}{3} ln2$
  3. $t = \dfrac {m}{b} - \dfrac {1}{2} ln2$
  4. $t = \dfrac {m}{b} \times \dfrac {1}{2} ln2$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

$\dfrac {1}{\sqrt {2}} = e^{-bt/m}$
$ln \sqrt {2} = \dfrac {bt}{m}$
$t = \dfrac {m}{b} \times \dfrac {1}{2} ln2$.

Multiple choice free, damped and forced oscillations free, forced and damped oscillations oscillations oscillation and waves physics

The periodic vibrations of a body of constant amplitude in the absence of any external force on it are called

  1. Forced vibrations

  2. Free vibration

  3. Damped vibrations

  4. All
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Forced vibrations: External force is acting on the body. 
Free vibration: Constant amplitude and no external force.
Damped vibration: Amplitude is not constant, it keeps on decreasing due to environmental factors of the system like air resistance.  
Therefore, correct option is B. 

Multiple choice free, damped and forced oscillations free, forced and damped oscillations oscillations oscillation and waves physics

The tendency of one object to force another adjoining or interconnected object into vibration motion is referred to as a 

  1. forced vibration.

  2. damped vibration

  3. loudness

  4. pitch
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The tendency of one object to force another adjoining or interconnected object into vibrating motion is referred to as a forced oscillation.

Multiple choice free, damped and forced oscillations free, forced and damped oscillations oscillations oscillation and waves physics

If a force is continually or repeatedly applied to keep the oscillation going, it is called 

  1. forced oscillator.

  2. free oscillatior

  3. damped oscillatior

  4. none of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When a periodically repetitive and oscillatory force acts on an object, then the object is forced to oscillate with the frequency of the periodic force. Such oscillation is known as forced oscillation. When an object is displaced from its mean position and allowed to vibrate along its mean position then the object vibrates with its own natural frequency. This is known as free vibration or oscillation. And an oscillation in which the amplitude goes on decreasing with time is known as damped oscillation.

Multiple choice free, damped and forced oscillations free, forced and damped oscillations oscillations oscillation and waves physics

When we push a child in a swing, the amplitude of the oscillation

  1. decreases

  2. increases

  3. remains same

  4. none of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

By pushing a child on a swing a driving force is applied which forces the swing and the child in the forward direction. The gravitational force acts as a restoring force and pulls back the child to the original position. These two forces together set them into an oscillatory motion. By pushing the child the amplitude, that is the maximum displacement, increases.

Multiple choice free, damped and forced oscillations free, forced and damped oscillations oscillations oscillation and waves physics

The orbital motion of the earth, around the sun is 

  1. periodic but not oscillatory

  2. oscillatory but not periodic

  3. neither periodic not oscillatory

  4. both periodic and oscillatory
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The orbital motion of the earth around the sun is not an oscillatory motion as it is not a two and fro motion about a mean position. But it is a periodic motion.