A light ray traveling form rarer to denser medium suffers a phase change of__________________?

A. 60°
B. 90°
C. 180°
D. 45°

Diffraction effect is____________________?

A. More for a round edge
B. Less for a round edge
C. More for a sharp edge
D. Less for a sharp edge

A diffraction grating has 500 lines per mm. Its slit spacing or grating element will be equal to ____________________?

A. 500 mm
B. 5 x 10-3 mm
C. 2 x 10-5 mm
D. 2 x 10-3 mm

When light incident normally on thin film the path difference depends upon ________________?

A. Thickness of the film only
B. Nature of the film only
C. Angle of indidence only
D. All thickness nature and angle of incidence

Light reaches the earth form sun in nearly____________________?

A. 15 minutes
B. 10 minutes
C. 8 minutes
D. 8 minutes 30 seconds

According to Einstein light travels form one place to another in the form of ________________?

A. Waves
B. Particles
C. Photons
D. It was not his discovery

Central spot of Newtons rings __________________?

A. Bright
B. Dark for large wavelength
C. Dark
D. Bright for large wavelength

The locus of all points in a medium having the same phase of vibration is called____________________?

A. Crest
B. Trough
C. Wavelength
D. Wave front

In a plane polarized light _________________?

A. Vibration in all direction
B. Vibration in two mutually perpendicular directions
C. Vibration take place in a direction perpendicular to the direction of propagation of light
D. No vibration at all

Which one of the following cannot be polarized ?

A. Radio waves
B. Ultraviolot rays
C. X-rays
D. Sound waves