Question

# Find the position of the final image of the object O after three successive reflections taking first reflection on m1.

A
12.5 cm in front of mirror m1.
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
10 cm in front of mirror m1.
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
12.5 cm in front of mirror m2.
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
10 cm in front of mirror m2.
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

## The correct option is A 12.5 cm in front of mirror m1. For first reflection at mirror m1, u=−15 cm f=−202=−10 cm So, 1v+1u=1f ⇒1v−115=−110 ⇒1v=−130 ⇒v=−30 cm This first image will act as the object for the plane mirror m2. For second reflection at plane mirror m2, u=−(40−30)=−10 cm So, v=+10 cm This second image will act as the virtual object for the mirror m1. For third reflection at mirror m1, u=−(40+10)=−50 cm f=−202=−10 cm So, 1v+1u=1f ⇒1v−150=−110 ⇒1v=−225 ⇒v=−12.5 cm Thus, the final image is formed at 12.5 cm in front of mirror m1.

Suggest Corrections
0
Explore more