Question

State the postulates of cartesian sign convention used for reflection by spherical mirrors

Answer 1

( 1 All distancesuld be measured from the pole . The distances measure in the direction of incident light, to be taken positive and measured in the opposite direction of incident light to be taken negative.

( 2 )The new cartesian sign convention is same as that for spherical mirrors .

( 3 ) The difference is that the distances are measured from the optical centre .

( 4 ) According to the sign convention, the focal length of a convex lens is positive and that of a concave lens is negative