Question

an object placed 36cm from a converging lens of focal length 24cm, forms a real image which is 6m high. what is the height of the object​

Answer 1

1 / f = 1 / o + 1 / i thin lens equation

1 / i = 1 / f - 1 / o = 1/24 - 1/36 = (36 - 24) / (36 * 24)

i = (36 * 24) / 12 = 72 cm

M = -i / o = -72 / 36 = -2

M = -I / O

O = -M * I = -2 * 6 = -12 cm

object = -2 * 6 cm high = -12 (object is inverted)

Check:

1 / 24 = 1 / 72 + 1 / 36 using top equation