Gravitational Field Intensity

Topic Content:

Gravitational field strength is the gravitational forceThe force of gravity, or gravitational force, pulls objects with mass toward each other. More per unit mass at a particular point.

Gravitational field strength, g = \( \frac{Gravitational \; force}{mass} \\ = \frac{F}{m}\)

F = mg

The gravitational field strength (g) is also known as acceleration due to gravity. The unit of g is N/kg and is constant at a particular location.

Gravitational field strength, g, is a vector quantityVector quantities are quantities with magnitude and direction. Examples of vector quantities include displacement, velocity, position, force, and torque. More; The direction of g is always towards the centre of the body creating the gravitational field.

Variation of g with Distance (r):

The earth is a sphere of mass M_e and radius r_e . We can take the distance between the centres of mass of Earth and an object on its surface to be the radius of Earth, provided that its size is much less than the radius of Earth.

The attractive force of the earth of mass (M_e ) on another mass (m) is related to distance (r_e ) from the earth by:

 F = \( \frac{GM_em} {r_{e}^{2}}\)………… (1)

• M_e is the mass of the Earth
• m is the mass of the object on the earth’s surface
• r