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I am Lyosha [343]

4 years ago

14

You lay a mirror flat on the floor with one edge against a wall and aim a laser at the mirror. The ray reflects from the mirror

and strikes the wall. The plane of the incident and reflected rays is perpendicular to the wall. The ray from the laser strikes the mirror 30.7 cm from the wall, and the reflected ray strikes the wall 30.1 cm above the mirror. Find the angle of incidence of the laser ray on the mirror.

1 answer:

joja [24]4 years ago

4 0

Answer:

the angle of incidence θ is 45.56 º

Explanation:

Given data

strikes the mirror before wall x = 30.7 cm

reflected ray strikes the wall y = 30.1 cm

to find out

the angle of incidence θ

solution

let us consider ray is strike at angle θ so after strike on surface ray strike to wall at angle 90 - θ

we will apply here right angle triangle rule that is

tan( 90 - θ) = y /x

tan( 90 - θ) = 30.1 / 30.7

90 - θ = tan^-1 (30.1/30.7)

90 - θ = 44.4345

θ = 45.56 º

the angle of incidence θ is 45.56 º

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