Question

An object of 5 centimetre is placed perpendicular to principal axis of concave lens of focal length 10 centimetre is distance of object from optical centre of the lens is 20 CM determine the position size and nature of the image formed using the lens formula

Answer 1

O=-5cm ( negative )

f=+10cm ( positive )

u=-20cm ( negative )

using lens formula,

1/f = 1/v - 1/u

1/10 = 1/v - (-1/20)

1/10 = 1/v + 1/20

1/v = 1/10 - 1/20

1/v = 2-1/20

1/v = 1/20

v = +20 which is positive so image is formed in front of the lens.

•POSITION -- 20 cm in front of lens.

•NATURE -- virtual , erect and and same size as that of object.

•SIZE -- same size as that of object.

HOPE IT HELPS...