Question

An object is placed $12 \,cm$ to the left of a converging lens of focal length $8 \,cm$. Another converging lens of $6\, cm$ focal length is placed at a distance of $30 \,cm$ to the right of the first lens. The second lens will produce

• A. No image
• B. A virtual enlarged image
• C. A real enlarged image
• D. A real smaller image

Answer 1

Answer: (C)

For lens (1) $\frac{1}{f}=\frac{1}{v}-\frac{1}{u} $
$\Rightarrow \frac{1}{(+8)}=\frac{1}{v}-\frac{1}{(-12)}$
$\Rightarrow v=24\, cm$, i.e., Image $A' B'$ is obtained $6 \,cm$ before the lens $2$ or at the focus of lens $2$ . Hence final image formed by lens $2$ will be real enlarged and it is obtained at $\infty$.