Question 127: Ray Optics

Question

The following figure represents two biconvex lenses $$L_1$$ and $$L_2$$ having focal length $$10 \mathrm{~cm}$$ and $$15 \mathrm{~cm}$$ respectively. The distance between $$L_1$$ & $$L_2$$ is :

Accepted Answer

Parallel rays are focussed by convex lens and viceversa.
$$\begin{aligned}
	herefore \quad L_1 L_2 & =f_1+f_2 \
& =10+15=25 \mathrm{~cm}
\end{aligned}$$

Answer

25 cm

Answer

35 cm

Answer

10 cm

Answer

15 cm

Ray Optics

The following figure represents two biconvex lenses $L_1 and L_2 having focal length 10 \mathrm{~cm} and 15 \mathrm{~cm} respectively. The distance between L_1 & L_2$ is :

Choose the correct answer: