Question

An object 6cm high is placed at a distance of 18cm from a convex lens of focal length 6cm. Find position of the image and the height of the image.

Answer 1

h = 6cm

u = -18cm

f = 6cm

Let ha represent height of image.

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

$= > \frac{1}{6} = \frac{1}{v } + \frac{1}{18}$

$= > \frac{1}{v} = \frac{1}{6} - \frac{1}{18} = \frac{3 - 1}{18} = \frac{2}{18} = \frac{1}{9}$

$= > v = 9cm$

$= > m = \frac{v}{u} = \frac{ha}{h}$

$= > ha = \frac{v \times h}{u} = \frac{9 \times 6}{ - 18} = - 3$

Position of image is 9cm Infront of the lens and Height of the image is 3cm and is inverted.

Hope this answer helps you ^_^ !