Question

An object 5 cm tall is placed 1 m from a concave spherical mirror which has a radius of curvature of 20 cm. The size of the image is

• A. 0.11 cm
• B. 0.50 cm
• C. 0.55 cm
• D. 0.60 cm

Answer 1

Answer: (C)

0.55 cm

Answer 2

By using $\frac { I } { O } = \frac { f } { f - u }$

Here $O + 5 \mathrm {~cm}$ $f = - \frac { R } { 2 } = - 10 \mathrm {~cm}$,

So, $\frac { I } { + 5 } = \frac { - 10 } { - 10 - ( - 100 ) }$

$\Rightarrow$ I = – 0.55 cm.