Mass: Unit - Kilogram (kg) - ‘The quantity of matter in a body.’ The mass of a body is a measure of how difficult it is to start or stop, (“a body”, in this context, means a substance. Any substance a gas, a liquid or a solid).
Acceleration: It is the rate of change of velocity. The change may be in magnitude or direction or in both. Thus, a body moving along a circular path at constant speed has acceleration.
Momentum: Unit - Mass x Velocity (kg-m/s) - ‘The quantity of motion possessed by a body’. The tendency of a body to continue in motion after being placed in motion.
Centre of Gravity (CG): The point through which the weight of an aircraft acts. (a) An aircraft in flight is said to rotate around its CG. (b) The CG of an aircraft must remain within certain forward and aft limits, for reasons of both stability and control
