CBSE
Multiple Choice QuestionsA person uses spectacles of power + 2 D. He is suffering from
myopia
presbyopia
astigmatism
hypermetropia
A convex lens made up of a material of refractive index µ1 is immersed in a medium of refractive index µ2 as shown in the figure. The relation between µ1 and µ2 is
µ1 < µ2
µ1 > µ2
µ1 = µ2
A plane mirror produces a magnification of
zero
- 1
+ 1
between 0 and + 1
The focal length of the objective and eye lenses of a microscope are 1.6 cm and 2.5 cm respectively. The distance between the two lenses is 21. 7 cm. If the final image is formed at infinity, then the linear magnification is
11
110
1.1
44
If a flint lens glass of dispersive power 0.066 renders achromatic to a convex lens of crown glass of focal length 60 cm and dispersive power 0.033, then its focal length is
− 60 cm
+ 60 cm
− 120 cm
+ 120 cm
An astronomical telescope arranged for normal adjustment has a magnification of 6. Ifthe length ofthe telescope is 35cm, then the focal length of objective and eye piece respectively, are
30 cm, 5 cm
5 cm, 30 cm
40 cm, 5 cm
30 cm, 6 cm
White light is incident on the interface of glass and air, as shown in the figure. If green light is just totally and internally reflected then the emerging ray in air contains
all colours
yellow, orange and red
violet, indigo and blue
all colours except green
In a pond of water, a flame is held 2 m above the surface of water. A fish is at depth of 4 m from water surface.Refractive index of warer i . The apparent height of the lame from the eyes of fish is
5.5 m
6 m
A thin prism placed in air produces minimum deviation of 4° in a light ray. If the prism 8 m is immersed in water, then the minimum deviation produced by it is
3°
5°
2°
1°
The magnification produced by the objective lens and the eye lens of a compound microscope are 25 and 6 respectively. The magnification of this microscope is
25
50
150
200
