An object 5.0 an in length is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 an. Find the position of the image, its nature and size.

Question

Philoid · Accepted Answer

Here, Object distance, u = -20 cm (to the left of mirror)

Image distance, v = ? (To be calculated)

Radius of curvature, R = +30cm (It is a convex mirror)

So, Focal length,

Now, putting these values of u and applying formula:

We get:

Thus, the position of image is 8.57 cm behind the mirror (on its right side). Since the image is formed behind the convex mirror, therefore, the nature of image is virtual and erect.

Now,

For a mirror, Magnification, m =

So, m = - = + 0.42

Also, Magnification, m =

So, +0.42 =

h₂ = 0.42×5.0 = 2.1 cm

Thus, the size of image is 2.1 cm.