Question

Find the power of a lens forms a real image 3 cm high of an object 1 cm high. If the separation of
object and image is 16 cm.
diaoram to​

Answer 1

h2 = -3 cm (real image)

h1 = 1 cm

-u + v = 15 cm

m = v/u = h2/h1

(15 + u)/u = -3/1

15 + u = -3u

u = -3.75 cm

v = 15 + u = 15 + (-3.75) = 11.25 cm

1/v – 1/u = 1/f

1/11.25 – 1/-3.75 = 1/f

f = 2.82 cm

● Hence verified ●