Question

an object of height 5 centimetre is placed perpendicular to the principal axis of a concave lens of focal length 10 centimetre. if the distance of the object from the optical centre of the lens is 20 centimetre determine the position, nature and size of the image ​

Answer 1

Answer:

Explanation:

h = 5cm

f = -10

u = -20

from lens formula we have,

1/f = 1/v - 1/u

1/v = 1/f + 1/u

1/v = 1/-10 + [1/-20]

1/v = 1/-10 - 1/-20

1/v = -3/20

Therfore , v = -20/3 cm

magnification:-

m = h'/h = v/u

Therefore,

h'/h = v/u

h'/5 = -20/3 x -20

h' = -20 x 5/-20 x 3

   = 5/3

   = 1.67cm

NATURE :- VIRTUAL &INVERTED

SIZE :-1.67cm

POSITION :- -20/3cm