Question

if the angle of deviation is right angle then a) angle i ,angle r and angle a are acute angle, b) angle of incidence will be zero ,c) the sum of angle of incidence and reflection is equal to angle of deviation ,d) the angle of deviation is a right angle​

Answer 1

According to the law of reflection, the angle of incidence is equal to the angle of refraction.

That is, ∠i=∠r. Let it be x.

In this case, the difference between the angle of incidence and angle of refraction is 90 degrees.

Given, ∠i+∠r = 90 degrees

or, x+x=90

0

or, x=45

0

Hence, the angle of incidence is 45

0

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Answer By shreyas