Question

An object is placed at a distance of 30 cm from a concave lens of focal length 15 cm. find position and nature of the image formed by the lens.

Answer 1

Hey dear here is ur answer. Hope it helps you. Mark it as brainliest please.

Given u=-30 cm; f =-15
1/f=1/v-1/u
1/-15+1/-30=1/v
1/v=1/-15-1/30
1/v=-3/30
v=-10 cm

Characteristics of image are

a. The image formed is virtual.

b. It is erect.

c. It is diminished in size.

d. The image is formed at a distance of 10 cm from the optical center of the concave lens on the same side of the object.

Answer 2

You should already know that a concave lens produces a virtual, erect diminished image. The only question is whereabouts? and how diminished?

Using Real Is Positive RIP Convention, u=30 and f=-15

1/u + 1/v = 1/f

1/30 + 1/v = -1/15

1/v = -1/15 - 1/30 = -3/30 = -1/10

v = -10 M=v/u = -1/3

So image is erect, virtual, 1/3 size of object, and 10 cm from the lens, (between lens and object)