Question

a double convex lens has two surfaces of equal radii' R and refrative index n=1.5 find the focal length 'f'.



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Answer 1

Answer:

Hey Buddy here's ur answer

Answer 2

Explanation:

Given 

Radius of curvature =R

focal length =f

Refractive index,  μ=1.5

From lens maker's formula

$$\cfrac{1}{f}=(\mu -1)\left[ \cfrac { 1 }{ { R }_{ 1 } } -\cfrac { 1 }{ { R }_{ 2 } }  \right] $$

$$\cfrac{1}{f}=(1.5-1)\left[ \cfrac { 1 }{ R } +\cfrac { 1 }{ R }  \right] $$

=0.5×R2

f1=R1

f=R