The space around an object within which its force of gravitation is experienced is termed as gravitational field.

**Gravitational Field Strength or Intensity:**

The gravitational field intensity at a point is described as the force experienced by a unit mass located at that point.

**Intensity of the field felt by a test mass:**

Let M be the mass of an object around which a gravitational field occurs. Let m be a test mass located in this field. The test mass is so selected that it does not influence the gravitational field. The arrow over \(\overrightarrow{E}\)

A force \(\overrightarrow{F}\)

\( \Rightarrow \overrightarrow{E} = \frac {\overrightarrow{F}}{m} \)

\(\overrightarrow{E}\)

\(\Rightarrow \overrightarrow{E} = \frac{\overrightarrow{F}}{m} = \frac{m.\overrightarrow{a}}{m} = \overrightarrow{a}\)

If the test mass m were free to move, it would move with acceleration towards M. Therefore, \(\overrightarrow{a}\)

The intensity is described as the free acceleration experienced by a trial mass at that point.

**Units Of Gravitational field:**

The units in the

- The C.G.S. system is dyne gm
^{-1}or cms^{-2}

- SI system is Nkg
^{-1}or ms^{-2}

If M is the mass of the Earth, then \(\vec{E}=\frac{m\vec{g}}{m}=\vec{g}\)

Stay tuned with Byju’s to explore interesting topics on gravitation, acceleration and many more. Join us and fall in love with learning.