Question

An object is kept at a distance of 5m in front of a spherical mirror, which forms its erect image at a distance of 2m from the mirror. What is the magnification? Is the mirror concave or convex?
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Answer 1

According to the Question

Image Formed if Erect.

Which means the image is Virtual

Then we use Magnification Formula

m = $\sf\dfrac{ - v}{u}$

So, we will Substitute the Value in this equation

=> m = $\sf\dfrac{ - 2}{ - 5}$

=> m = $\sf\dfrac{2}{5}$

=> m = 4

$\therefore \sf{ the \: magnification \: of \: the \: mirror \: is \: 4cm}$

Which is Positive

So, The Mirror is Convex.

Answer 2

Answer:

Given:-

Object distance,u = 5m

image distance ,v = 2m

Image formed is erect .

To Find:-

Magnification ,m

Solution:-

According to the Question

The mirror formed erect image . It means that image formed is virtual . Using magnification formula

m = -v/u

where

m denote magnification

v denote image distance

u denote object distance

Substitute the value we get

m = -2/-5

m = 2/5

m = +0.4

Hence, the magnification of the mirror is 0.4 .

here, the magnification is positive . So the mirror is convex .