JEE Main 20169 Apr, Morning shiftPhysicsHardOptics190× since 2002
To find the focal length of a convex mirror, a student records the following data :
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Object
Pin
Convex
Lens
Convex
Mirror
Image
Pin
22.2 cm
32.2 cm
45.8 cm
71.2 cm
The focal length of the convex lens is f₁ and that of mirror is f₂. Then taking index correction to be negligibly small, f₁ and f₂ are close to :