Figure represents a glass plate placed vertically on a horizontal table with a beam of unpolarised light falling on its surface at the polarising angle of `57^@` with the normal. The electric vector in the reflected light on screen S will vibrate with respect to the plane of incidence in a

Options

A. vertical plane
B. Horizontal plane
C. Plane making and angle of `45^(@)` with the vertical
D. Plane making an angle of ` 57^(@)` with the horizontal

Answer

A

Explanation

When an unpolarised beam of light is incident on a glass slab at the polarising angle, the reflected beam is completely plane polarised in a plane perpendicular to the plane of incidence. Light is an e.m. wave, in which the `vecE` vector is the dominant vector.
`:. ""vecE` vector in the reflected light will vibrate w.r.t. the plane of incidence in a vertical plane.