Question

Shown below are three plane mirrors M 1, M 2, M 3, inclined to each other 110 and 120 degree respectively, reflecting a ray of light incident at point of incidence O making an angle of 30 degrees with the mirror. Work out the following angles. a)The angle "u"? b) The angle "r"?

Answer 1

Explanation:

Answer

Correct option is

D

δ=360

o

−2δ

δ

1

=180−2i

1

δ

2

=180−2i

2

Also,θ+(90−i

1

)+(90−i

2

)=180

=θ+180−i

1

−i

2

=180

=θ=i

1

+i

2

S

net

=δ

1

+delta

2

=360−2(i

1

+i

2

)

=360−2(θ)

=360−2θ