12.3 IMAGE LOCATION BY SPHERICAL MIRROR FORMULA
How can we tell about the nature of image (whether image is real or imaginary, inverted or erect) formed in a mirror? How can we tell about the size of the image compared with the size of the object? To answer these questions, one method is graphical or ray diagram. But, we can also answer these questions by using a mathematical formula called the mirror formula defined as:
Mirror formula is the relationship between object distance p, image distance q from the mirror and focal length f of the mirror. Thus we can write mirror formula as:
(12.1)
Equation (12.1) is true for both concave and convex mirrors. However, following sign conventions should be followed to apply this equation for solving problems related to mirrors.