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
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
With both eyes open, a person's field of view is about :
90°
150°
180°
360°
Linear magnification produced by a concave mirror may be :
less than 1 or equal to 1
more than 1 or equal to 1
less than 1,more than 1 or equal to 1
less than 1 or more than 1
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 miror used by a dentist to examine the teeth of a person is :
convex
concave
plane
both concave and convex
The refraction of light is commonly known as
bending
scattering
reflection
interference
A person cannot see the distant objects clearly (though he can see the near by objects clearly).He is suffering from the defect of vision called :
cataract
hypermetropia
myopia
presbyopia
Myopia can be corrected by using
concave lenses
contact lenses
prismatic lenses
convex lenses
