Mass

Full Title or Meme

Mass is the concept that enables us to say that an object (or an idea) is weighty or massive.

Context

• Issac Newton needed a mathematical definition of what caused gravity and so defined it thus

  The quantity of matter is the measure of the same, arising from its density and bulk conjucntly ... It It is this that I mean hereafter everywhere under the name body, or mass. And the same is known by the weight of each body, for it is proportional to the weight, as i have found by experiments on pendulums, very accurately made, which shall be shown hereafter.

• There are these types of mass as commonly defined:

1. rest,
2. inertial. F = ma, resistance to acceleration
3. gravitational. F = m₁m₂r²