The wave-front due to source situated at the infinity is
(A) Spherical
(B) Cylindrical
(C) Plane
(D) Rectangular
(A) Spherical
(B) Cylindrical
(C) Plane
(D) Rectangular
(C) Plane
The wavefront due to a source situated at infinity is
(a) spherical
(b) cylindrical
(c) planar
(d) circular
A wavefront of a wave has direction with wave motion
(A) Parallel
(B) Perpendicular
(C) opposite
(D) at any angle θ
The colours on the soap bubble is due to
(a) Interference
(b) Diffraction
(c) Polarisation
(d) Reflection
The parameter of light wave which remain same after refraction
(A) speed
(B) frequency
(C) wavelength
(D) none of these
The condition for Fraunhoffer diffraction from a single slit is that the light wave-front incident on a slit should be
(A) Spherical
(B) Cylindrical
(C) Plane
(D) Rectangular
Which of the following is conserved when light waves interfere?
(a) phase
(b) intensity
(c) amplitude
(d) none of these
The locus of all the points vibrating in same phase of oscillation is called
(A) Wavelet
(B) Wavefront
(C) Wavetrain
(D) Rays
The current sensitivity of a Galvanometer can be increased by decreasing-
a) Magnetic field B
b) No. of turns N
c) Torsional constant k
d) Area of the coil A
The amount of work required to increase the distance between -6µC and 4µC from 6 cm to 18 cm will be :
(a) 1.8 J
(b) 2.4 J
(c) 1.8 µJ
(d) 2.4 µJ
Three charges each equal to 2 μC are placed at the corners of an equilateral triangle. If force between any two charges is 2F, then the net force on either will be:
Which of the following statements indicates that light waves are transverse?
(a) Light waves can be polarised
(b) Light waves can show interference
(c) Light waves undergo diffraction
(d) They travel in the vacuum
When a compact disc is illuminated by a source of white light , colored lines are observed. This is due to
I. Interference
II. Diffraction
III. Dispersion
IV. Refraction
An optically active compound
(a) rotates the plane of polarised light.
(b) changes the direction of polarised light.
(c) does not allow plane polarised light to pass through.
(d) none of these.