Geometrical OpticsHard
Question
An eye specialist prescribes spectacles having combination of convex lens of focal length 0 cm in contact with a concave lens of focal length 25 cm. The power of this lens combination is diopters is
Options
A.+ 1.5
B.- 1.5
C.+ 6.67
D.- 6.67
Solution
The focal length of combination is given by
or
cm = - 
∴ Power of the combination in dioptres,
P = - 
= - 1.5
or
cm = - ∴ Power of the combination in dioptres,
P = -
= - 1.5
Create a free account to view solution
View Solution FreeMore Geometrical Optics Questions
For a transparent prism, if the angle of minimum deviation is equal to its refracting angle, the refractive index $n$ of...A ray of light strikes a cubical slab surrounded by air as shown in the figure. Than the geometrical path length travers...A ray of light passes through equilateral Prism (μ =1.5 ) such that angle of incidence is equal to angle of emergen...A fish rising vertically up towards the surface of water with speed 3 ms-1 observes a bird diving vertically down toward...A mark at the bottom of a liquid appears to rise by 0.1 m. The depth of the liquid is 1 m. The refractive index of the l...