Tag: wave optics

Questions Related to wave optics

Light transmitted in Nicol prism is

  1. unpolarized

  2. plane polarized

  3. circularly polarized

  4. elliptically polarized


Correct Option: B
Explanation:

In Nicol Prism, ordinary ray is eliminated and Extra-ordinary ray, which is plane polarized, is transmitted through the prism.

In, the case of linearly polarized light the magnitude of electric field vector

  1. vary periodically with time

  2. increases and decreases linearly with time

  3. does not change with time

  4. is parallels to the direction of propagation


Correct Option: A
Explanation:

In general equation for electric field vector for linearly polarized light is given as $\left| \vec { E }  \right| ={ E } _{ o }\sin { \left( { \omega t }-{ kx } \right)  } $ which indicate that its varies periodically with respect to time.

Such that it is perpendicular to the direction of propagation

Two beams, A and B of plane polartice light with mu;a;y perpendicular plances of po;arixation are seen triugh  polaroid from the position wjen the beam B has xero intensity a rotation of polato thorough 30 makes the two beams appear equally bright if the intial  Intensites of the two beams are 1 and 1 rtespctively the n equls 

  1. 3

  2. $\frac { 3 }{ 2 } $

  3. 1

  4. $\frac { 1 }{ 3 } $


Correct Option: A

Optically active substances are those which

  1. produce polarized light

  2. rotate the plane of polarization of the polarized light.

  3. produce double refraction

  4. convert a plane polarized light into circularly polarized light.


Correct Option: B
Explanation:

Optically active substance by definition are substances which can rotate the plane of polarization of polarized light.


Answer. B) rotate the plane of polarization of polarized light.

If for a calcite crystal, $\displaystyle\mu _0$ and $\displaystyle\mu _e$ are the refractive indices of the crystal for O-ray and E-ray repectively, then along the optic axis of the crystal

  1. $\displaystyle\mu _0$ = $\displaystyle\mu _e$

  2. $\displaystyle\mu _0$ > $\displaystyle\mu _e$

  3. $\displaystyle\mu _0$ < $\displaystyle\mu _e$

  4. None of these


Correct Option: A
Explanation:

In calcite crystal, only along the optical axis, the refractive indices of the crystal are equal for O-ray and E-ray

Optically active substances are those substances which 

  1. produces polarised light

  2. produces double refraction

  3. rotate the plane of polarisation of polarised light

  4. converts a plane polarised light into circularly polarised light


Correct Option: C
Explanation:

By definition, optically active substances are those which can rotate the plane of polarisation of polarised light.

Polaroid glass is used in sun glasses because

  1. it reduces the light intensity to half on account of polarisation

  2. it is fashoinable

  3. it has good colour

  4. it is cheaper


Correct Option: A
Explanation:

Polaroid glass cut glare and haze by reducing the light intensity to half on account of polarisation, so that eyes are more comfortable and viewer can see better, therefore they are used in sun glasses.

A nicol prism is based on action of

  1. refraction

  2. double refraction

  3. dichroism

  4. both (b) and (c)


Correct Option: D
Explanation:

When a ray of light enters nicol prism, it splits into two plane polarised light in mutually perpendicular direction. One of this light undergoes total reflection and absorption whereas other comes out as a plane polarised light.

If a polaroid is kept in the path of an uniformly unpolarised light, the intensity of the transmitted light to the intensity of the light when the polaroid was not kept in its path is.

  1. 1

  2. $\dfrac{1}{2}$

  3. $\dfrac{1}{\sqrt 2}$

  4. $\dfrac{1}{2\sqrt 2}$


Correct Option: B
Explanation:
The component of the electric vector of all the electric vectors of unpolarised light in one direction only = $\dfrac {E _0}{\sqrt {2}} $
And, $I \propto E^2 \Rightarrow I = \dfrac {I _0}2 $

A Nicol prism can be used.

  1. For producing and analysing polarised light

  2. Only to analyse polarized light

  3. Only to produce polarized light

  4. None of the above


Correct Option: A
Explanation:

A Nicol prism is use to produce and analyse the polarised light.