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
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 light ray traveling form rarer to denser medium suffers a phase change of__________________?
(A) 60°
(B) 90°
(C) 180°
(D) 45°
appearance of colour in thin films is due to ____________________?
(A) diffraction
(B) dispersion
(C) interference
(D) polarization
The velocity of light was determined accurately by_______________?
(A) Newton
(B) Michelson
(C) Huygen
(D) Young
Two sources of light are coherent if they emit rays of_______________?
(A) same wavelength
(B) same amplitude of vibration
(C) same wave length with constant phase difference
(D) same amplitude and 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
Central spot of Newtons rings __________________?
(A) bright
(B) dark for large wavelength
(C) dark
(D) bright for large wavelength
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
Light reaches the earth form sun in nearly____________________?
(A) 15 minutes
(B) 10 minutes
(C) 8 minutes
(D) 8 minutes 30 seconds