The focal length of a spherical mirror of radius of curvature 30 cm is :
10 cm
15 cm
20 cm
30 cm
A converging lens has a focal length of 50 cm.The power of this lens is :
+0.2 D
-2.0 D
+2.0 D
-0.2 D
The refraction of light is commonly known as
bending
scattering
reflection
interference
A virtual image is one which
can be taken on a screen
cannot be taken on a screen
sometimes can be and sometimes cannot be taken on a screen
is formed only by a concave mirror
What type of lens will form when a tumbler is filled with water?
Bi convex
Concavoconvex
Plano convex
Biconcave
What is called reciprocal of focal length of a lens ?
Power
Radius
Centre of curvature
Focus
The ratio of the sine of the angle of incidence to the sine of angle of refraction is constant and is called
Malu's law
Snell's law
Optical density
Relative density
A man is using concave mirror for shaving.If his face is 20 cm from the mirror having magnification 2,what will be the radius of curvature of the mirror?
60 cm
80 cm
50 cm
40 cm
The sideways reversal of image by plane mirror is:
Lateral inversion
Parallax
Optical illusion
Optotune
A diverging lens is used in :
a magnifying glass
a car to see objects on near side
spectacles for the correction of short sight
a simple camera
