Gravitational Field Strength

We know that every body of the universe attracts every other body. The region around a body in which any other particle experiences gravitation animation due to this body is called the gravitational field.

Gravitational Field Strength:

The gravitational field strength at any point in a gravitation animation is defined as the gravitational force per unit mass, when infinitesimal mass is placed at that point.

If an infinitesimal (very small) mass m experiences a gravitational force F at a point, then gravitational field strength at that point, Infinitesimal mass means that the original gravitation animation of field strength does not change due to presence of this mass.