The refractive index of the material of the prism is √3, then the angle of minimum deviation of the prism is
30°
45°
60°
75°
Pick out the longest wavelength from the following types of radiations.
Blue light
Gamma rays
X-rays
Red light
Which of the following phenomena exhibits particles nature of light?
Interference
Diffraction
Polarisation
multiple total internal reflections
2 convex lenses
2 concave lenses
1 convex, 1 concave lens
1 convex and 1 plane mirror
A body is located on a wall. Its image of equal size is to be obtained on a parallel wall with the help of a convex lens. The lens is placed at a distance d ahead of second wall, then the required focal length will be
more than but less than
less than
If fv and fn are the focal lengths of a convex lens for violet ad red light respectively and FV and FR are the focal lengths of concave lens for violet and red light respectively, then we have
fV < fR and FV > FR
fV < fR and FV < FR
fV > fR and FV > FR
fV > fR and FV < FR
A transparent cube contains a small air bubble. Its apparent distance is 2 cm when seen through one face and 5 cm when seen through other face. If the refractive index of the material of the cube is 1.5, the real length of the edge of cube must be
7 cm
7.5 cm
10.5cm
A man is 6 ft tall. In order to see his entire image, he requires a plane mirror of minimum length equal to
6 ft
12 ft
2 ft
3 ft
An astronomical telescope of ten fold angular magnification has a length of 44 cm. The focal length of the objective is
440 cm
44 cm
40 cm
Light travels through a glass plate of thickness t and refractive index μ. If c is the speed of light in vaccum, the time taken by light to travel this thickness of glass is
μtc
tc/μ
t/μc
μt/c
