Question

Explain the sign convention for spherical mirrors.

Answer 1

Sign convention is used to assign signs to the variables related to the analysis of spherical mirrors. This simplifies the numerical analysis related to mirrors and reduces the chance of errors. According to the sign convention:

• All distances are measured from the pole.
• Distances to the right of the pole are taken as positive and to the left as negative.
• Distances above the principal axis are taken as positive and below it are taken as negative.