[3 Mark Questions]

Question

Define magnification produced by a spherical mirror. What does its value indicate? Also mention its formula. Discuss about its sign for real and virtual image.

Vidyadip · Accepted Answer

→ Magnification produced by a given spherical mirror is defined as a ratio of height of image $\left(h^{\prime}\right)$ to the height of object $(h)$. It is shown by symbol $m$. Thus by definition.
$
m=\frac{h^{\prime}}{h}
$
→ Magnification produced by a spherical mirror gives how many times size of image is as compared to size of object.
→ Generally, object is placed upright above the principal axis and so its height $h$ is taken positive.
→ Since real image is inverted, its height $h$ ' is taken negative and so for real image, value of $m$ is obtained negative by definition.
→ Conversely, since virtual image is erect, its height $h^{\prime}$ is taken positive and so for virtual image value of $m$ is obtained positive by definition.
n Thus, when magnification is negative, image is real and when magnification is positive, image is virtual.
→ For spherical mirrors, formula of magnification is as follows.
$
m=-\frac{v}{u}
$
where $v$ and $u$ denote image distance and object distance respectively. (which are to be determined as per new cartesian sign convention system).

Answer

Need a full question paper?

Explore more

Similar questions

light-reflection and refraction — Science STD 10 — Question

Answer

Need a full question paper?

Explore more

Similar questions