Question

A 2.0 cm tall object is placed perpendicular to the principal axis of a convex lens of focal
length 10 cm. The distance of the object from the lens is 15 cm. Find the nature, position,
and size of the image. Also, find its magnification.​

Answer 1

Answer:

Object's size (h1) = 2 cm

Focal length of convex lens (f) = 10 cm

Object distance from the lens (u) = -15 cm

Image distance ( v) = ?

Image size (h2) = ?

We know,

1/v - 1/u= 1/f

1/v = 1/f + 1/u

1/v = 1/10 - 1/15

1/v = 1/30

Thus, v = 30 cm

Now, v = 30 cm, 'v' is positive, that means the image is formed on the right side of the lens. That's why it is REAL and INVERTED.

Now, magnification =?

Linear magnification (m) = Size of image / Size of object = h2 / h1 = v/u

m = h2/2 = 30/-15

m= h2 × -15 = 30×2

m = -15 h2 = 60

h2 = 60 / -15

h2 = -4 cm

Size of the image = -4 cm

It's in negative , that means that the image is INVERTED.