

InterviewSolution
Saved Bookmarks
1. |
A luminous object is placed 20 cm from surface of a convex mirror and a plane mirror is set so that virtual images formed in two mirrors coincide. If plane mirror is at a distance of 12cm from object. Then focal length of convexA. 20cmB. 15cmC. 10cmD. 5cm |
Answer» Correct Answer - d. For convex mirror, `u+v=12xx2=24cm` (because for plane mirror, distance of object `=` distance of image). Also, here for the convex mirror `u=20cm`, therefore `v=4cm` . Hence, using `(1)/(v)+(1)/(u)=(1)/(f)` We find `f=5cm` |
|