A diverging lens is used in :
a magnifying glass
a car to see objects on rear side
spectacles for the correction of short sight
a simple camera
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
A young man has to hold a book at arm's length to be able to read it clearly.The defect of vision is :
astigmatism
myopia
presbyopia
hypermetropia
The focal length of a spherical mirror of radius of curvature 30 cm is :
10 cm
15 cm
20 cm
30 cm
Which type mirror is used in box-type solar cooker?
Spherical mirror
Convex mirror
Plane mirror
Concave mirror
SI unit of power is
metre
horse power
dioptre
watt
The sum of the reciprocals of object distance and image distance is equal to the
focal length of a mirror
reciprocal of the focal length
radius of curvature
magnification
A concave mirror cannot be used as :
a magnifying mirror
a torch reflector
a dentist's mirror
a rear view mirror
The term "accomodation" as applied to the eye,refers to its ability to :
control the light intensity falling on the retina
erect the inverted image formed on the retina
vary the focal length of the lens
vary the distance between the lens and retina
