Question

Focal length of a plane mirror is :

• A. Small
• B. Infinite
• C. Very small
• D. Long

Answer 1

Answer:

B. Infinite

• Focus is the point where parallel rays after reflection meet or get focused.
• If parallel rays fall on mirror, then after reflection they are still parallel and these rays appear to meet at infinity so the focus of a plane mirror is infinity.
• 1. Plane mirrors are defined as flat, one side-polished surface that can reflect the light rays.
  2. Plane mirror is a flat surface that reflects most of the light falling on it.
  3. The image formed by a plane mirror is erect, same size and virtual.
  4. The image formed by a plane mirror is literally inverted.