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9. Ray optics abd optical instruments — Physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 SciencePhysics9. Ray optics abd optical instruments1 Mark
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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