**Start revising A-level & GCSE with 7 million other students**

# Forces in a gravitational Fields

## You are here

***Please note: you may not see animations, interactions or images that are potentially on this page because you have not allowed Flash to run on S-cool. To do this, click here.***

## Forces in a gravitational Fields

If the field strength at a point in a field is the force per unit mass, it doesn't take a huge leap to realise that the total force acting on an object of mass, M, in a gravitational field will be

F = M.g

**Apply that to the equation for field strength in a radial field to get:**

* Note:* that all the points made about the field strength equation are just as valid about the force equation. It is a vector, it's an inverse square relationship, it depends on the masses involved, etc.

However, force is not a property of the field. It depends on what is inside the field.