Question

. A convex lens has a focal length of 10 cm. The object of height 0.4cm is placed at a distance of 5 cm from the optical center . The height of the image will be

Answer 1

Answer:0.8 cm

Explanation:

Given )

f =10cm

h =0.4cm

u = -5cm

By lens formula

1/f =1/v -1/ u

1/10 = 1/v -(-1/5)

1/ 10 = 1/v + 1/5

1/10 -1/5 = 1/v

-10 cm =v

Negative sign shows that the image is formed on the same side of the lens where object is placed

By linear magnification ,,

h of image / h of object = v/u

H / 0.4cm = -10/ - 5cm

H = 0.4 ×2

H= 0.8cm

Hence the image is of height 0.8 cm