MCQ
A point object is placed mid-way between two plane mirrors distance $'a'$ apart. The plane mirror forms an infinite number of images due to multiple reflection. The distance between the nth order image formed in the two mirrors is
  • A
    $na$
  • $2na$
  • C
    $na/2$
  • D
    $n^2\, a$

Answer

Correct option: B.
$2na$
b
(b) From above figure it can be proved that separation between nth order image formed in the two mirrors $= 2na$

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