JEE PHYSICS MCQ: ELECTROMAGNETIC WAVES

1 Medium

1 of 1

Application +4 | -1

An electromagnetic wave of intensity

50\,\,W{m^{ - 2}}

enters in a medium of refractive index ‘n’ without any loss. The ratio of the magnitudes of electric fields and the ratio of the magnitudes of magnetic fields of the wave before and after entering into the medium are respectively, given by

View answer and explanation

Correct option: D

\left( {\sqrt n ,\frac{1}{{\sqrt n }}} \right)

Option D

\left( {\sqrt n ,\frac{{1}}{{\sqrt n }}} \right)

is correct because the ratio of electric fields is

\sqrt{n}

and the ratio of magnetic fields is

\frac{1}{\sqrt{n}}

after entering the medium.

More Questions from ELECTROMAGNETIC WAVES

Practice All Chapter MCQs →

Statement I: Sound waves are not electromagnetic waves.

Statement II: Sound waves require a material medium for propagation. For a plane electromagnetic wave propagating in x-direction, which one of the following combination gives the correct possible directions for electric field

(E)

and magnetic field

(B)

respectively? Assertion: The relative velocity of two photons travelling in opposite directions is the velocity of light.

Reason: The rest mass of photon is zero Intensity of electromagnetic wave will be The rms value of the electric field of the light coming from the Sun is

720\;N/C

. The average total energy density of the electromagnetic wave is Methane is a greenhouse gas because