Weight

What is mass?

The amount of ‘stuff’ in an object. For any given object, this will have the same value anywhere in the universe

What type of quantity is Mass?

A scalar quantity

How is mass measured?

kilograms (kg) with a mass balance

What is weight?

The force acting on an object due to gravity (the pull of gravitational force on the object)

What is weight measured in?

newtons (N) using a calibrated spring balance (or newton meter)

What is the centre of mass, and how does it relate to weight?

The centre of mass is the point in an object where the entire mass can be considered to be concentrated (all the mass of the object is treated as if it were located at a single point). In a uniform gravitational field (the force of gravity is the same everywhere in the field/pulls at the same strength at every point), the weight of the object can be thought of as acting at this point, simplifying the analysis of its motion

What is the equation for weight?

Mass (kg) x gravitational field strength (N/kg)

How does gravitational field strength vary?

With location. Its stronger the closer you are to the mass causing the field (and more massive objects create stronger fields). This means that the weight of an object changes with its location