JEE Main | 2014Geometrical OpticsHard
Question
Thin convex lens made from crown glass 
has focal length f. When it is measured in two different liquids having refractive indices 
and 
it has the focal lengths f1 and f2 respectively. The correct relation between the focal lengths is
has focal length f. When it is measured in two different liquids having refractive indices and it has the focal lengths f1 and f2 respectively. The correct relation between the focal lengths is Options
A.f1 = f2 < f
B.f1 > f and f2 becomes negative
C.f2 > f and f1 becomes negative
D.f1 and f2 both become negative
Solution
By Lens maker′s formula
⇒ f1 = 4f & f2 = - 5f
⇒ f1 = 4f & f2 = - 5f
Create a free account to view solution
View Solution FreeMore Geometrical Optics Questions
A ray OP of monochromatic light is incident on the face AB of prismABCD near vertex B at an incident angle of 60o (see f...The wavelength of light in two liquids ′x′ and ′y′ is 3500 and 7000 , then the critical angle wi...y = sin πx ; cos π x π ⇒ = ± 1an 45o = 1 = 2 cosπxcos πx = ⇒ π x = ∴...The number of points in (- ∞,∞), for which x2 - xsinx - cosx = 0, is...A ray of light is incident on the surface of separation of a medium with the velocity of light at an angle 450 and is re...