# Gravitational field strength – formula, definition, & derivation

Last updated on December 2nd, 2022 at 05:08 pm

A gravitational field is a region where you find gravity. More precisely, the gravitational field is defined as a region of space where a mass experiences a force because of its mass. In this post, we will find out more about the **Gravitational field strength with its definition, derivation, and formula**.

**What is the gravitational field strength? **| define **gravitational field strength**

Gravitational field strength gives a measure of how much force a body will experience in the gravitational field. **It is defined as the gravitational force per unit mass experienced by a small test mass placed in the gravitational field. **

So if a test mass, m, experiences a force F at some point in space, then the field strength, g, at that point is given by g =

*F*/m

Unit: The

**unit of Gravitational field strength g is N/kg, and it is a vector quantity.**See how to get the Dimensional formula of gravitational field strength.

**Gravitational field strength** formula derivation | Derivation of **Gravitational field strength formula**

Let’s consider the Gravitational field around a spherical object of mass M.

The gravitational force experienced by the mass, m is given by **F = G Mm/r^2**

So the field strength at this point in space, g = Gravitational force per unit mass =*F/ m*

So,

**g = G**. This is the formula of

*M*/r^2**Gravitational field strength**.

Also Read: **Law of Gravitation & derivation of the formula for Gravitational force**

## Write down the formula of **Gravitational field strength**

**The gravitational field strength** at a point in a gravitational field = **g = G M/r^2**

G = Universal Gravitational constant

M is the mass that is the source of the gravitational field

r is the distance of the test point from the source mass

**Suggested reading** – calculate the* value* of the **Gravitational field strength**.

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