Gravity

Gravitational Field

A gravitational field as a region in which an object experiences a force due to gravitational attraction.

Gravitational Field Strength

1. The gravitational field strength at a point in the gravitational field is the gravitational force acting on a mass of 1 kg placed at that point.
2. The unit of gravitational field strength is N/kg.
3. The gravitational field strength is denoted by the symbol "g". g = Gravitational Field Strength
F = Force acted on an object
m = mass of the object.

Gravitational Acceleration

1. The gravitational acceleration is the acceleration of an object due to the pull of the gravitational force.
2. The unit of gravitational acceleration is ms-2
3. Gravitational acceleratio is also denoted by the symbol "g".

Important notes:

1. Gravitational acceleration does not depend on the mass of the moving object.
2. The magnitude of gravitational acceleration is taken to be 10ms-2.

Gravitational Field Strength vs. Gravitational Acceleration

1. Both the gravitational field strength and gravitational acceleration have the symbol, g and the same value (10ms-2) on the surface of the earth.
2. When considering a body falling freely, the g is the gravitational acceleration.
3. When considering objects at rest, g is the Earth’s gravitational field strength acting on it.

Weight

1. The weight of an object is defined as the gravitational force acting on the object.
2. The SI unit of weight is Newton (N)

Differences between Weight and Mass

 Weight Mass Depends on the gravitational field strength Independent from the gravitational field strength Vector quantity Scalar Quantity Unit Newton (N) Unit: Kilogram (kg)