NEET UG PHYSICS MCQ: RAY OPTICS

1 Hard

1 of 1

Application +4 | -1

The dispersive power of crown and flint glasses are 0.02 and 0.04 respectively. What is the focal length of a convex lens of crown glass which makes an achromatic doublet with a concave lens of flint glass of focal length

80 \mathrm{~cm}?

View answer and explanation

Correct option: D

40 \mathrm{~cm}

Option D (

40 \mathrm{~cm}

) is correct because it satisfies the condition for achromatic doublet, where the net dispersion is zero.

More Questions from RAY OPTICS

Practice All Chapter MCQs →

An object 5 cm tall is placed

\mathrm{1}\,\,\mathrm{m}

from a concave spherical mirror which has a radius of curvature of

\mathrm{20}\,\,\,\mathrm{cm}

. The size of the image is Red colour is used for danger signals because A ray of light is incident on the hypotenuse of a right-angled prism after travelling parallel to the base inside the prism. If

\mathrm{\mu }

is the refractive index of the material of the prism, the maximum value of the base angle for which light is totally reflected from the hypotenuse is Statement-A: The minimum distance between an object and its real image formed by a convex lens is

2{f}

.

Statement-B: The distance between an object and its real image is minimum when its magnification is -1. Assertion: We cannot produce a real image by plane or convex mirrors under any circumstances.
Reason: The focal length of a convex mirror is always taken negative. If both the object and image are at infinite distance from a refracting telescope its magnifying power will be equal to