Question

A convex lens of focal length $f$ is cut into two halves as shown. Light rays parallel to the principal axis are incident on one half of the lens (say $L_1$) This will form an image at

• A. $f$
• B. $\frac{f}{2}$
• C. $f$
• D. $\frac{f}{4}$

Answer 1

The correct option is A $f$

If a convex lens is cut into two halves horizontally, then focal length does not change.

So, light parallel to principle axis will converge at focus.

Hence, $\left(a\right)$ is the correct answer