Between which two points of concave mirror should an object be placed to obtain a magnification of

Between which two points of concave mirror should an object be placed to obtain a magnification of:

(a) −3

(a) An object, in front of a concave mirror, should be placed between the latter's centre of curvature (C) and focus (F) to obtain a magnification of −3.
(b) An object, in front of a concave mirror, should be placed between the latter's focus (F) and the pole (P) to obtain a magnification of +25. 
(c) An object, in front of a concave mirror, should be placed beyond the latter's centre of curvature (C) to obtain a magnification of −0.4.

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Between which two points of a concave mirror should an object be placed to obtain a magnification of -3 ?

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Between which two points of concave mirror should an object be placed to obtain a magnification of a 3 b + 2.5 c 0.4

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Between which two points of a concave mirror should an object be placed to obtain a magnification of 3 ?

(a) To obtain a magnification of $-$3

An object should be placed in front of a concave mirror, between the centre of curvature $(C)$ and focus $(F)$ to obtain a magnification of $-$3.

Explanation

Given:

Magnification, $m$ = $-$3

Here, magnification is with the negative sign $(-)$, which implies that the image is real and inverted.

$\because m>1\Rightarrow $ the size of the image is greater than 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 between the centre of curvature $(C)$ and focus $(F)$ in front of the mirror.

(b) To obtain a magnification of $+$2.5

An object should be placed in front of a concave mirror, between the focus $(F)$ and the pole $(P)$ to obtain a magnification of +2.5.

Explanation

Given:

Magnification, $m$ = $+$2.5

Here, magnification is with the positive sign $(+)$, which implies that the image is virtual and erect.

$\because m>1\Rightarrow $ the size of the image is greater than 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 between the focus $(F)$ and the pole $(P)$ in front of the mirror.

(c) To obtain a magnification of $-$0.4

An object should be placed in front of a concave mirror, beyond the centre of curvature $(C)$ to obtain a magnification of $-$0.4.

Explanation

Given:

Magnification, $m$ = $-$0.4

Here, magnification is with the positive sign $(-)$, which implies that the image is real and inverted.

$\because m<1\rightarrow>

In the case of the concave mirror, both of the above-mentioned conditions are only possible when the object is placed beyond the centre of curvature $(C)$ in front of the mirror.