Physics

Wave Motion

536 Questions

Wave motion questions cover the principles of traveling and stationary waves, including their equations and intensities. The topics explore interference patterns, phase differences, and electromagnetic radiation speeds. Mastery of these concepts is vital for physics sections in engineering and civil services examinations.

Wave interferenceStanding wavesPhase differenceElectromagnetic radiationWave equations

Wave Motion Questions

Multiple choice physics properties of waves longitudinal and transverse waves travelling waves types of waves

A transverse wave travels along z-axis. The particles of the medium moves

  1. Along the z-axis

  2. Along the x-axis

  3. Along the y-axis

  4. In the x-y plane
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The particles of medium moves perpendicular to the direction of the propagation of the wave in the case of transverse wave.

In the given question, a transverse wave travels along z-axis. All the lines in the X-Y plane are perpendicular to z-axis, hence the particle of the medium must move in the X-Y plane.
The correct option is D.

Multiple choice physics properties of waves longitudinal and transverse waves travelling waves types of waves

The particle displacement of a travelling longitudinal wave is represented by S=S (x,t). The midpoints of a compression zone and an adjacent rarefaction zone are represented by the letter 'C' and 'R' Which of the following is true?

  1. ${ \left| \partial S/\partial x \right| } _{ C }={ \left| \partial S/\partial x \right| } _{ R }$
  2. ${ \left| \partial S/\partial t \right| } _{ C }={ \left| \partial S/\partial t \right| } _{ R }=0$
  3. ${ \left( pressure \right) } _{ C }-{ \left( pressure \right) } _{ R }=2{ \left| \partial S/\partial x \right| } _{ C }x$ Bulk modulus of air.

  4. Particles of air are stationary mid-way between 'C' and 'R'.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In a longitudinal wave, the displacement gradient (dS/dx) represents the strain. At the center of a compression (C) and a rarefaction (R), the displacement is zero, but the magnitude of the strain (the slope of the displacement curve) is equal.

Multiple choice physics properties of waves longitudinal and transverse waves travelling waves types of waves

Disturbance $y(x, t)$ of a wave propagating in the position x-direction is given by $y = \dfrac {1}{1 + x^{2}}$ at time $t = 0$ and by $y = \dfrac {1}{[1 + (x - 1^{2})]}$ at $t = 2\ s$, where $x$ and $y$ are in meters. The shape of the wave disturbance does not change during the propagation. The velocity of wave in m/s is

  1. $2.0$
  2. $4.0$
  3. $0.5$
  4. $1.0$
Reveal answer Fill a bubble to check yourself
B Correct answer
Multiple choice physics properties of waves longitudinal and transverse waves travelling waves types of waves

In gases which wave cannot propagate

  1. standing wave

  2. longitudinal wave

  3. transverse wave

  4. none
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Transverse waves cannot propagate in gases because there are no forces to cause motion perpendicular to the direction of the wave. A transverse wave propagates in a solid because each atom of the solid has an "equilibrium location" where the forces on it from all its neighboring atoms balance. If one atom is pulled out of its equilibrium location by a disturbance, it will tend to be pulled back to that location. However, when it's out of its equilibrium location, it pulls its neighbors out of their equilibrium locations too, and so on down the line. The result is that a transverse wave disturbance propagates through the material.

Multiple choice physics properties of waves longitudinal and transverse waves travelling waves types of waves

For propagation of a mechanical wave, the medium must possess

  1. inertia

  2. conductivity

  3. plasticity

  4. elasticity
Reveal answer Fill a bubble to check yourself
A,D Correct answer
Explanation
  • MEDIUM SHOULD BE ISOTROPIC: The properties of the medium should be the same in all directions.
  • ELASTICITY : The medium should have elasticity so that the particles return back to their original positions after being displaced.
  • INERTIA : This allows the particles to store kinetic energy.
  • MINIMUM FRICTION : So that the particles oscillate and the wave travels for a sufficiently long time and distance.
  • these were the properties required for propagation of mechanical waves , so the answer is A and D.
Multiple choice physics properties of waves longitudinal and transverse waves travelling waves types of waves

Water waves are an example of waves that involve

  1. longitudinal motions.

  2. transverse motions.

  3. a combination of both longitudinal and transverse motions

  4. some unknown type of motions,
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Water waves are an example of waves that involve a combination of both longitudinal and transverse motions. As a wave travels through the waver, the particles travel in clockwise circles. The radius of the circles decreases as the depth into the water increases.

so the answer is C.

Multiple choice physics properties of waves longitudinal and transverse waves travelling waves types of waves

Which of the following statements are true for wave motion ?

  1. Mechanical transverse waves can propagate through all mediums

  2. Longitudinal waves can propagate through solids only

  3. Mechanical transverse waves can propagate through solids only

  4. Longitudinal waves can propagate through vacuum
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$1.$ Mechanical transverse waves cannot propagate through all the medium. They can only propagate through solids not in gas or a liquid because there is no mechanism for driving motion perpendicular to the propagation of the wave.

$2.$ Longitudinal wave can propagate through all type of medium.
$3.$ Mechanical transverse wave can propagate through solids only.
$4.$ Longitudinal wave cannot propagate through vaccum.
Hence, option $C$ is correct.