A biconvex thick lens is constructed with glass (μ = 1.50). Each of the surfaces has a radius of 10 cm and the thickness at the middle is 5 cm. Locate the image of an object placed far away from the lens.
Biconvex lens with each surface has a radius (
Thickness of lens (t) = 5 cm
Refractive index of lens ==1.50
Position of object =
At first refraction occurs at A
By using lens equation:
⇒
⇒
⇒
Now, the second refraction occurs at B
Object distance =u= (30-5) = 25 cm (a virtual object)
Radius
So, (by using lens equation)
So, the image is formed 9.1 cm further from the 2nd surface of the lens.