A luminous object is placed at a distance of $30\ cm$ from the convex lens of focal length $20\ cm$. On the other side of the lens, at what distance from the lens a convex mirror of radius of curvature $10\ cm$ be placed in order to have an upright image of the object coincident with it

Question

Dr. Abubacker · Accepted Answer

(c) For lens $u = 30\ cm,\ f = 20\ cm,$ hence by using
$\frac{1}{f} = \frac{1}{v} - \frac{1}{u} \Rightarrow \frac{1}{+ 20} = \frac{1}{v} - \frac{1}{- 30} \Rightarrow v = 60\ cm$
The final image will coincide the object, if light ray falls normally on convex mirror as shown. From figure it is seen clear that separation between lens and mirror is $60 - 10 = 50\ cm$

Q. A luminous object is placed at a distance of $30\ cm$ from the convex lens of focal length $20\ cm$. On the other side of the lens, at what distance from the lens a convex mirror of radius of curvature $10\ cm$ be placed in order to have an upright image of the object coincident with it

Explanation

Reviewed by Dr. Abubacker

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