Question

An object of height 4cm is placed at a distance of 50cm from a convex lens of focal length 20cm. Find the position, nature and image size

Answer 1

h=4cm

u=-50cm

f=20cm

1\f=1\v-1\u

1\20+1\-50=1\v

5+(-2)\100=1\v

3\100=1\v

1\33.3=1\v

therefore

33.3cm=v

m=v\u

m=33.3\-50

m=-0.66cm

therefore,

the image is real and inverted and diminished in size. Its located between 2F and F.

Hope this helps you

Regards Mihir.Thacker.