Question

find the angle deviation when two mirrors are perpendicular to each other​

Answer 1

Explanation:

as the both mirrors are perpendicular to each other....

hope it helps you...

Answer 2

Answer:

It is always 180°.

Explanation:

Actually it is a property that the total angle deviation of incident ray when two mirrors are perpendicular to each other is 180° irrespective of the angle of incidence on the first mirror.

Let's Prove It.

If you can see the above picture,

1. You can see that the angle of incidence (Let's denote it as i) is 40°.
2. So, the angle of reflection (Let's denote it as r) is also 40° (because i =r).
3. So, the angle below i should be 50° because the normal ray is perpendicular to a surface. So, 90° - 40° = 50°.
4. So, the angle of deviation (denoted as δ) of first mirror is 50° × 2 = 100°.
5. Now, let's find the δ of second mirror.
6. For that, we have to take the angle below r which is 50°.
7. As you know, that angle between the mirrors are perpendicular to each other (90°), so the angle below the second i (Let's represent the angle of incidence of second mirror as second i) is 180° - (90° + 50°) = 40° (Angle Sum Property of Triangle).
8. Now, the angle below the second r will also be 40°.
9. So, the δ of 2nd mirror is 40° × 2 = 80°.
10. So finally, the total δ of 2 mirrors is 100° + 80° = 180°.

That's how it is proved that the total angle deviation of incident ray when two mirrors are perpendicular to each other is 180° irrespective of the angle of incidence on the first mirror.