If a magnification of, −1 (minus one) is to be obtained by using a converging mirror, then the object has to be placed:- between pole and focus
- at the centre of curvature
- beyond the centre of curvature
- at infinity
(b) at the centre of curvature
Explanation
Given:
Magnification, $m$ =$-$1
Here, magnification is with the positive sign $(-)$, which implies that the image is real and inverted.
$\because m=1\Rightarrow $ the size of the image is the same as that of the object.
In the case of the concave mirror, both of the above-mentioned conditions are only possible when the object is placed at the centre of curvature $(C)$ in front of the mirror.
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