Question

Concave mirror and convex mirror having equal focal lengths 2f are placed on same principal axis. If the object AB is placed between these mirros, find the height ratio of the images of this object on two mirrors `H_(x)//H_(y) = ?`

A. `1//2`
B. `3//2`
C. `4//3`
D. `1//1`

Answer 1

Correct Answer - B
We use following equation to find height of the object.
`H_("image")//H_("object") = f//d`, where `d_(r)` is the distance between object and focal point of the mirror. Distance between object and focal point to the mirror x is `d_(fx) = 8f` and distance between object and focal point of the mirror y is `d_(fy) = 12f`. Let height of the object is h,
`H_("image")//h = 2f//8f`
`H_("image")x = h//4`
`H_("image")y//h = 2f//12f`
`H_("image")y = h//6`
`H_("image")//H_("image"Y) = 3//2`