NCEA Level 3: Physics - Mechanics

Acceleration

Rate of change of velocity of an object. Can result from a change in speed or direction

Angular acceleration

Rate of change of angular velocity of a rotating body

Angular displacement

Angle described at the centre of the circle by a moving body along a circular path

Angular frequency

Frequency in radians per second

Angular momentum

Mass x angular velocity for an object in circular motion

Angular Velocity

Rate of change of angular displacement of a rotating body

Balanced forces

Number of forces acting on a body and the resultant force is zero

Centripetal force

Force required to keep and object moving in a circle

Conservation of energy

When energy is transformed from one type of energy into another, the total energy before and after are always the same

Conservation of momentum

The total momentum of a group of a closed system remains constant in the absence of external forces

Dampen

Any effect causing the loss of energy during SHM

Displacement

The change in the position of an object in a particular direction

Elastic collision

Collision where kinetic energy is conserved

Equilibrium position

Where displacement is zero in SHM

Force

______ changes the state of rest or of uniform motion, the direction of motion or the shape and size of a body

Impulse

Change in momentum caused by an external force

Inelastic collision

Collision where kinetic energy is not conserved

Inertia

Property of matter that causes it to resist change in its state of rest or uniform motion

Mass

The quantity of matter in a body

Net force

The resulting force after all forces have been added using vectors

Newton

Amount of force to accelerate a 1kg mass at 1ms^-2

Newton's first law of motion

A body continues to be in a state of rest or uniform motion unless it is acted on by an external force

Newton's law of gravitation

Force between two particles is proportional to their masses and inversely proportional to the square of the distance between them

Newton's second law of motion

The rate of change is equal to force or force acting on a body is equal to mass x acceleration

Newton's third law of motion

Every action has an equal and opposite reaction

Rectilinear motion

Motion of a body in a straight line

Resonant frequency

The frequency of vibration of an elastic object that depends on the size, composition and shape of object

Restoring force

The force which moves an oscillating body back to its mean position whenever it is displaced

Simple Harmonic Motion

The vibratory motion where there is a restoring force opposite to an proportional to the displacement

Torque

Turning force (not applied through centre of mass)

Work

When a force acting on a body moves it