Question

What is the difference between G and g?

Answer 1

"G" is Newton's universal gravitational constant.The gravitational force between two bodies of masses m₁ & m₂, separated by a distance r is given by :

$F=G\frac{{m}_1.{m}_2}{{r}^2}$
The value of G is 6.67 × 10⁻ ¹¹ N.m²/Kg² . This is universal constant.

"g" is the the acceleration due to gravity.
It varies, even on the earth from place to place.
Average value of "g" may be taken as 9.807 m/s².

Answer 2

G is gravitational constant which has a value 6.67 × 10^-11

Whereas g is nothing but acceleration of an object caused due to gravity , its value is 9.8m/s² ,

You can calculate it by using :-

g = GM/R²

where , M = mass of earth

R = Radius of earth