Question

The magnification produced by a plane mirror is +1. What does this mean?

Answer 1

1. The magnification produced by a mirror is defined as the ratio of the size of the image to the size of the object, that is; $m=\frac{h_i}{h_0}$
2. If the magnification produced by a mirror is positive, it means the image is virtual and if the magnification produced by a mirror is negative it represents a real image.
3. The magnification produced by a plane mirror is +1, that is $+1=\frac{h_i}{h_o}\Rightarrow h_o=h_i$
4. Thus, the size of the image formed is exactly equal to the size of the object behind the mirror.

5. Positive magnification represents that the image is virtual and erect.

6. It is also known that, magnification$m=-\frac{v}{u}$ that is $+1=-\frac{v}{u}\Rightarrow -u=v$

7. It means that the image distance is equal to the object distance.