Question

# Find the distance between object (O) and final image formed after two successive reflections. Take the first reflection on mirror M1 having radius of curvature 20 cm

A
20 cm
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
15 cm
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
40 cm
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
35 cm
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
Open in App
Solution

## The correct option is C 35 cmFor 1st reflection on m1 Sign convention: Taking positive along the incident ray. f=−R2=−202=−10 cm u=−15 cm Let first image by the mirror M1 is formed at distance v Using mirror formula, ⇒1v+1(−15)=1(−10) ⇒1v=115−110=2−330 ∴v=−30 cm ⇒ First image formed by concave mirror lie at I1 and I1 will form another image at I2 by plane mirror. Thus, object distance for plane mirror, |NI1|=10 cm Now the distance between object and image formed by plane mirror at I2 is OI2=|NO|+|NI2| ∵|NO|=40−15=25 cm ∴OI2=25+10=35 cm

Suggest Corrections
0
Related Videos
Natural Phenomena
PHYSICS
Watch in App