Question

Find the distance and nature of the image formed by the concave mirror as shown in the figure.

• A. $-\frac{40}{3}\text{cm}$, Real image
• B. $-\frac{40}{3}\text{cm}$, Virtual image
• C. $+\frac{40}{3}\text{cm}$, Real image
• D. $+\frac{40}{3}\text{cm}$, Virtual image

Answer 1

The correct option is A $-\frac{40}{3}\text{cm}$, Real image

Given:
$u=+40\text{cm}$
$f=-20\text{cm}$
So, $\frac{1}{v}+\frac{1}{u}=\frac{1}{f}$
$\Rightarrow \frac{1}{v}+\frac{1}{40}=\frac{-1}{20}$
$\Rightarrow \frac{1}{v}=\frac{-3}{40}$
$\Rightarrow v=\frac{-40}{3}\text{cm}$
As the image is formed on the same side of the concave mirror, the image is real.