Show that the eccentricity of a planetary orbit can be written as

PHYSICS · Subjective · CBSE · Physics · Gravitation · Gravitation

Problem

Show that the eccentricity

e

of a planetary orbit can be written as

e=\dfrac{r_a-r_p}{r_a+r_p}

, where

r_a

and

r_p

denote the aphelion and perihelion distances respectively.