Jee Main
Geometrical Optics
JEE Main 2022 (Online) 25th July Evening Shift
INTEGER+4 / -12022
A convex lens of focal length 20 cm is placed in front of a convex mirror with principal axis coinciding each other. The distance between the lens and mirror is 10 cm. A point object is placed on principal axis at a distance of 60 cm from the convex lens. The image formed by combination coincides the object itself. The focal length of the convex mirror is ____________ cm.