Question

Two plane mirrors, nearly parallel, are facing each otherd1 = 2.2m apart as in (Figure 1) . You stand d2 = 1.8maway from one of these mirrors and look into it. You will see multiple images of yourself.

parta-how far away from you is the first image of yourself in the mirror in front of you?

partb-How far away from you is the second image of yourself in the mirror in front of you?

partc-How far away from you is the third image of yourself in the mirror in front of you?

<---------- d2----------> person

   <---------------d1------------->

Answer 1

a). Plane Mirror has a property that distance of object remains equal to the distance of image.

Hence Image distance from Plane mirror will be v₁= d₂

   and Image Distance from the person will be D₁= 2(d₂)= 2(1.7)m = 3.4m (ANS)

b). Second Image of the person in front of mirror will be due to the reflection of the person from the mirror placed in back of him.

Thus For Ist reflection(from the back of the mirror), Image distance will be v'= (d₁-d₂)= (2.2-1.7)m= 0.5m

Then Object Distance for the mirror in front will be u₂= d₁ +v'= (2.2+0.5)m= 2.7m

Second Image distance in front mirror will be v₂= u₂= 2.7m

And the Second Image distance from the person in front mirror will be D₂= v₂+d₂= (2.7+1.7)m= 4.4m (ANS)

Answer 2

part a answer is 1.8+1.8=3.60 m

part b answer is 2.6+1.8=4.40 m

part c answer is 6.2+1.8=8.00 m