Geometrical OpticsHard
Question
Two lenses in contact made of materials with dispersive powers in the ratio 2 : 1, behaves as an achromatic diverging focal length 10 cm. The individual focal length of the lenses are :
Options
A.5 cm, - 10 cm
B.- 5 cm, 10 cm
C.10 cm, -20 cm
D.- 20 cm, 10 cm
Solution
= 0 (condition for a chromaticism)ω1 : ω2 = 2 : 1(Given)
⇒ f1 : f2 = - 2 : 1.................. (i) (for fullfill condition)
by (i) & (ii) f1 = - 10 cm & f2 = - 5 cm
Create a free account to view solution
View Solution FreeMore Geometrical Optics Questions
A par axial beam is incident on a glass (n = 1.5) hemisphere of radius R = 6 cm in air as shown the distance of point of...Two plane mirrors M1 and M2 are inclined to each other at 70o A ray imminent on the mirror M1 at an angle falls on M2 an...The image of an object, formed by a plano-convex lens at a distance of 8 m behind the lens, is real and is one-third the...The magnifying power of a simple microscope is 6. The focal length of its lens in metres will be, if least distance of d...When light is refracted from air into glass...