Question

An object is placed perpendicular to the prinupal axis of a convex bens of focal leugth 20cm at a distance of 30cm fim the leus - find (i) the position (ii) magnificator and (iii) the nature of the image formed.​

Answer 1

V = 20cm

U = 30cm

By lens formula

1/v - 1/4 = 1/6

1/v - (1/-30) = 1/20

1/v + 1/30 = 1/20

1/v = 1/20 - 1/30

1/v = 3-2/60

1/v = 1/60

i) Magnification, m = hi/no = v/u

ii) m = v/u = 60/-30 = -2

Nature, magnification is negative hence, It is real inverted.