A double convex lens made of glass of refractive index `1.56` has both radii of curvature of magnitude `20 cm`. If an object is placed at a distance of `10 cm` from this lens, find the position of image formed.

Options

A. `22.86` same side of the object
B. `22.86` opposite side of the object
C. `44.89` same side of the object
D. `44.89` opposite side of the object.

Answer

A

Explanation

Here, `R_(1)` = 20 cm, `R_(2)` = -20 cm, `u`= -10 cm and `mu` = 1.56
Using lens maker's formula,
`(1)/(f)=(1.56-1)((1)/(20)+(1)/(20))rArrf=(20)/(0.56xx2)=17.86` cm
Now, from lens equation,
`" "v=(uf)/(u+f)=(-10xx17.86)/(-10+17.86)=-22.86` cm
Since `v` is negative, the image will be formed on the same side as that of object.