Question

A 3 cm high object is placed at a distance of 30cm from a concave lens of Focal length 15cm find the image size of the image nature of the image

Answer 1

Explanation:

Given,

Object Distance,u=-30cm

Focal length,f=-15cm

Lens is concave

Object height,h=+3cm

To Find:

Image Distance, v=?

Image Height, h'=?

By lens formula,

1/f=1/v-1/u

1/-15=1/v-1/-30

-1/15-1/30=1/v

-2-1/30=1/v

-3/30=1/v

-1/10=1/v

So,v=-10cm

By Magnification Law,

m=v/u=h'/h

Thus,

-10/-30=h'/3

1/3=h'/3

h'=3/3

h'=1cm

THAT'S ALL ,I'VE DONE IT