Chapter 4 - Mass, Weight and Density

1. Mass

1.1. Definition: Mass is the amount of matter in a body.

1.2. SI unit: kilogram (kg)

1.3. Measurements: Electronic/Beam balance

1.4. Relations: Unlike weight, the mass of an object does not change with its location or shape.

1.5. Scaler Quantity

2. Weight

2.1. Definition: The weight of an object is the gravitational force acting on it.

2.2. SI unit: newton (N)

2.3. Measurements: Spring/Compression balance

2.4. Relations: Unlike mass, the weight of an object changes according to its location and its gravitational force.

2.5. Vector Quantity

3. Intertia

3.1. Definition: The inertia of an object refers to the reluctance of the object to change its state of rest or motion, due to its mass.

3.2. The mass of the object will affect its inertia. An object with a greater mass will have a greater inertia and thus making it harder for the objects to start moving, slow down, move faster or change direction.

4. Gravitational Field Strength

4.1. Definition: Gravitational Field Strength, g, is defined as the gravitational force acting per unit mass.

4.2. SI unit: newton per kilogram (N/kg)

4.3. Relation: The weight of an object depends on the amount of gravitational field force acting on it.