JEE PHYSICS MCQ: ELECTROMAGNETIC WAVES

1 Easy

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Understanding +4 | -1

Let the velocities of light in vacuum and glass are represented by

v

and

v_{\mathrm{g}}

. When electrons move through glass with a velocity

v_e

, there emitted a visible radiation in glass if

View answer and explanation

Correct option: A

v_e > v_g

Option A is correct because visible radiation (Cherenkov radiation) is emitted when a charged particle travels through a dielectric medium faster than the speed of light in that medium.

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