Question 52: Ray Optics

Question

A slanted object $A B$ is placed on one side of convex lens as shown in the diagram. The image is formed on the opposite side. Angle made by the image with principal axis is :

Accepted Answer

Location of image of A :-
$$\begin{aligned}
& \frac{1}{v}-\frac{1}{u}=\frac{1}{f} \Rightarrow \frac{1}{v}-\frac{1}{-30}=\frac{1}{20} \Rightarrow \frac{1}{v}=\frac{1}{60} \Rightarrow v=60 \mathrm{~cm} \
& 	herefore m=2
\end{aligned}$$
Since size of object is small wrt the location hence
$$\begin{aligned}
& d v=m^2 d u \Rightarrow d v=4 	imes 1=4 \mathrm{~cm} \
& h_i=m h_0 \Rightarrow h_i(d y)=2 	imes 2=4 \mathrm{~cm}
\end{aligned}$$
$	herefore$ Angle made with principle axis $=-45^{\circ}$

Answer

$-\alpha$

Answer

$-\frac{\alpha}{2}$

Answer

$-45^{\circ}$

Answer

$+45^{\circ}$

Ray Optics

A slanted object A B is placed on one side of convex lens as shown in the diagram. The image is formed on the opposite side. Angle made by the image with principal axis is :

Choose the correct answer: