. What is Cartesian Sign Convention.Write its formula
i. All distances are measured from the pole of the mirror. The pole is taken as the origin.
ii. The distances measured in the same direction as the incident light are taken as positive and those measured in the direction opposite to the direction of incident light are taken as negative.
iii. The heights measured upwards with respect to x-axis and normal to the principal axis (x-axis) of the mirror lens are taken as positive. The heights measured downwards are taken as negative.
iv. Focus is +ve in case of convex mirror while it is -ve in case of concave mirror for the following situation.