A convex lens has a focal length of 10cm. At which of the following distance should an object be placed in front of this convex lens so that it may act as a magnifying glass?
15cm
7cm
20cm
25 cm
If the image formed is always virtual, the mirror can be
concave or convex
concave or plane
convex or plane
only convex
Which of the following always diverge light rays?
convex mirror and plane mirror
concave mirror and convex mirror
concave lens and concave mirror
concave lens and convex mirror
Which of the following can form a virtual image which is always smaller than the object?
a. Concave mirror b. Concave lens c. Convex mirror d. Convex lens
A and B
B and C
A and C
B and D
The image formed by a spherical mirror is virtual. The mirror will be
concave
convex
either concave or convex
metallic
The splitting up of white light into seven colours on passing through a glass prism is called
refraction
deflection
dispersion
scattering
When an object is kep at any distance in front of a concave lens, the image formed is always
virtual, erect and magnified
virtual, inverted and diminished
virtual, erect and diminished
virtual, erect and same size as object
A virtual image larger than the object can be produced by a
concave lens
concave mirror
convex mirror
plane mirror
Whatever be the position of the object, the image formed by a mirror is virtual, erect and smaller than the object. The mirror then must be
plane
The image formed by a concave mirror is seen to be virtual, erect and larger than the object. The position of object must then be
between focal length and twice the focal length
far off (many times the focal length)
close to concave mirror (at less than focal length)
greater than twice the focal length
