A convex lens made of 5 different transparent materials is used to make an image of an object placed in front of it. The number of images formed will be :

(1) 2 

(2) 3

(3) 4

(4) 5

If the plane surface of a planoconvex lens is silvered, then it will behave as:
1. converging mirror
2. diverging mirror
3. plane mirror
4. may behave as (1) or (2)

Chromatic aberration of a lens can be corrected by

(1) Reducing its aperture

(2) Proper polishing of its surfaces

(3) Suitable combining it with another lens

(4) Providing different suitable curvature to its surfaces

A small air bubble is at the centre of a glass sphere of radii 5 cm. When it is viewed from outside what will be the position of the image?

Refractive index of glass is 1.5

(1) At the same place as that of object

(2) $\frac{10}{3}$ cm from the surface near the eye

(3) 7.5 cm from the surface of the sphere near the eye

(4) At infinity

The refractive indices of a prism for red, yellow and violet colours are 1.52, 1.57 and 1.62 respectively, then the dispersive power of the material of prism will be:

(1) 1.57

(2) $\frac{1}{5.7}$

(3) 5.7

(4) 1

The magnification of a compound microscope for the final image at least distance of distinct vision is 90. The magnification of the objective lens is 15. The value of the focal length of the eyepiece will be

(1) 5 cm

(2) 6 cm

(3) $\frac{1}{6}$ cm

(4) 12 cm

A terrestrial telescope is made by introducing an inverting lens of focal length $f_i$. The focal length of objective and eyepiece are $f_o and f_e$. Then the length of the telescope for normal adjustment is

(1) $f_o+f_e+f_i$

(2) $f_o+f_e+2f_i$

(3) $2f_o+f_e+f_i$

(4) $f_o+f_e+4f_i$

The reflected light wave and incident light wave differ each other by a phase angle of ${180}^0$, when

1. Light enters into glass from air

2. Light enters into air from glass

3. Light enters into glass from diamond

4. Light enters into water from glass

Converging rays are incident on a convex lens, the image formed

(1) May be virtual

(2) Must be virtual

(3) May be real

(4) Must be real

A small source of light is \(2\) m below the surface of a liquid of refractive index \(\frac{5}{3}.\) In order to block all the light coming out of the liquid surface, the minimum diameter of the displaced on the surface of the liquid is:
1. 3m
2. 4m
3. 6m
4. 1.5m