Question

an object is 6cm in size is placed at 50 cm in front of a concave mirror of focal length 30 cm. at what distance from a mirror should a screen be placed in order to obtain a sharp image. find the nature and size of the image

Answer 1

Explanation:

Given,

f = 30cm

u = - 50 cm

h = -6cm

Lens formula

\frac{1}{f}=\frac{1}{v}-\frac{1}{u}

\frac{1}{v}=\frac{1}{f}+\frac{1}{u}

\frac{1}{v}=\frac{1}{30}-\frac{1}{50}

v = +75cm

m = \frac{v}{u}=\frac{h_{1}}{h}

\frac{75}{-50}=\frac{h_{1}}{6}

h_{1 }=-9cm

Image formed is real, increased and enlarged.