FORM 4: 2.13 MEANINGS

ITEM	MEANING
DISTANCE	Distance is the total path length travelled from one location to another.
DISPLACEMENT	Displacement is the distance between two locations measured along the shortest path connecting them, in a specified direction.
SPEED	Speed is the rate of change of distance.
VELOCITY	Velocity is the rate of change of displacement.
ACCELERATION	Acceleration is the rate of change of velocity.
DECELERATION	Deceleration is the rate of decrease in speed in a specified direction.
INERTIA	The inertia of an object is the tendency of the object to remain at rest or, if moving, to continue its uniform motion in a straight line.
NEWTON’S FIRST LAW	Newton’s first law states that every object continues in its state of rest or of uniform motion unless it is acted upon by an external force.
MOMENTUM	Momentum is defined as the product of mass and velocity.
PRINCIPLE OF CONSERVATION OF MOMENTUM	Principle of conservation of momentum states that in the absence of an external force, the total momentum of a system remains unchanged.
BALANCED FORCE	When the forces acting on an object are balanced, they cancel each other out; the net force / resultant force is equal to zero.
NEWTON’S SECOND LAW OF MOTION	The acceleration produced by a net force on an object is directly proportional to the magnitude of the net force applied and is inversely proportional to the mass of the object. The direction of the acceleration is the same as that of the net force.
IMPULSE	Impulse is defined as the product of impulsive force and time interval.
	Impulse is also equal to the change of momentum.
IMPULSIVE FORCE	The large force that acts over a short period of time during collisions and explosions is known as impulsive force.
	Impulsive force can be defined as the rate of change of momentum in a collision or explosion.
FREE FALL	An object is falling freely when it is falling under the force of gravity only (free from the influence of other forces).
ACCELERATION DUE TO GRAVITY	Acceleration due to gravity is the acceleration of object falling freely.
GRAVITATIONAL FIELD	Gravitational field is a region around the earth in which an object experiences a force towards the centre of the earth.
GRAVITATIONAL FIELD STRENGTH	The gravitational field strength at a point is defined as the gravitational force acting on a 1 kg mass placed at that point.
WEIGHT	The weight of an object is defined as the gravitational force acting on the object.
RESULTANT FORCE	A resultant force is a single force that can represent the combined effect of two or more forces in magnitude and direction.
WORK	Work is defined as the product of the applied force and the displacement of an object in the direction of the applied force.
KINETIC ENERGY	Kinetic energy is the energy of an object due to its motion.
GRAVITATIONAL POTENTIAL ENERGY	Gravitational potential energy is the energy of an object due to its higher position in the gravitational field.
PRINCIPLE OF CONSERVATION OF ENERGY	The principle of conservation of energy states that energy can be transferred from one form to another, but it cannot be created or destroyed.
POWER	Power is defined as the rate at which work is done.
EFFICIENCY	Efficiency is defined as the percentage of the energy input that is transformed into useful energy.
ELASTICITY	Elasticity is the property of a material that enables it to return to its original shape and size when the force that was acting on it is removed.
HOOKE’S LAW	Hooke’s law states that the extension of a spring is directly proportional to the applied force provided that the elastic limit is not exceeded.
ELASTIC LIMIT	The elastic limit of a spring is defined as the maximum force that can be applied to a spring such that the spring will be able to be restored to its original length even though the force not longer acts on it.
ELASTIC POTENTIAL ENERGY	Elastic potential energy is the energy stored in a spring when it is extended or compressed.