CBSE
Multiple Choice QuestionsA fish, looking up through the water sees the outside world contained in a circular horizon. If the refractive index of water is 4/3 and the fish is 12cm below the surface of water, the radius of the circle in centimeter is
12 × 3 ×
12 × 3 ×
If Young's double slit experiment is performed in water instead of air, then
no fringes would be seen
fringe width would decrease
fringe width would increase
fringe width would remain unchanged
Two coherent light beams of intensity I and 4I are superposed. The maximum and minimum possible intensities in the resulting beam are
5 I and I
5 I and 3 I
9 I and I
9 I and 3 I
A lens of focal length 1 m forms Fraunhofer diffraction pattern of a single slit of width 0.04 cm in its focal plane. The incident light contains two wavelengths λ1 and λ2 . It is found that the fourth minimum corresponding to λ1 and fifth minimum corresponding to λ2 occur at the same point 0.5 cm from central maximum, then λ1 and λ2 are
400 nm, 500 nm
500 nm, 700 nm
700 nm, 500 nm
500 nm, 400 nm
In a single slit diffraction experiment, first minimum for λ1 = 660 nm coincides with first maxima for wavelength λ2 is
950 nm
610 nm
390 nm
440 nm
The maximum number of possible interference maxima for slit separation equal to twice the wavelength in Young's double-slit experiment, is
infinite
five
three
zero
Two cars A and B approach a stationary observer from opposite sides as shown in the figure hears no beats. If the frequency of the horn of the car B is 504 Hz, the frequency of horn of the car A will be
529.2 Hz
295.2 Hz
440.5 Hz
259.2 Hz
In Young's double-slit experiment, the angular width of fringe formed on a distance screen is 0.1°. If wavelength of light is 6000 , then spacing between the slits is
3.4 × 10-4 m
4.3 × 10-4 m
5.4 × 10-4 m
6.3 × 10-4 m
The blue colour of sky is explained by
reflection
scattering
polarisation
refraction
Mark the wrong statement regarding polarisation of light
The vibrations in a plane polarised light are perpendicular to the plane of polarisation
If a polarised light of intensity l0 , is passed through an analyser the intensity of light transmitted is I = l0 cos2 θ
Polarisation is the property of longitudinal wave
Tangent of polarising angle is equal to the refractive index of medium upon which the light is incident
