Question

If two plane mirrors are kept at 60° to each other, then the number of images formed by them is ______.

Options

• 5

• 6

• 7

• 8

Answer 1

If two plane mirrors are kept at 60° to each other, then the number of images formed by them is 5.

Explanation:

The number of images (n) of a point object maintained between two plane mirrors when they are inclined at an angle of θ is

n = `(360°)/theta-1`,  `("if"  (360°)/theta-1  "is even integer")`

∴ Number of images formed = `(360°)/(60°)-1` = 5