Question

an object is placed at a distance of 25cm from a convex mirror of focal length 20cm. Find the nature and position of the image ​

Answer 1

Answer:

The image is located 11.11cm and its nature is virtual and erect.

Explanation:

Given:

Object distance (u) = -25cm

Focal Length (f) = 20cm

By Mirror Formula,

⇒ 1/v + 1/u = 1/f

⇒ 1/v - 1/25 = 1/20

⇒ 1/v = 1/20 + 1/25

⇒ 1/v = 9/100

∴v = 100/9

    ≈ 11.11 cm

Since the value of the image distance is positive, the image is formed behind the mirror, ie. it is virtual and erect.

I hope that this helps you, mate!

Answer 2

Answer:

Explanation

Object distance (u) = -25cm

Focal Length (f) = 20cm

By Mirror Formula,

⇒ 1/v + 1/u = 1/f

⇒ 1/v - 1/25 = 1/20

⇒ 1/v = 1/20 + 1/25

⇒ 1/v = 9/100

∴v = 100/9

≈ 11.11 cm

Since the value of the image distance is positive, the image is formed behind the mirror, ie. it is virtual and erect.