W
Watt
The watt (W) is the SI Unit of power. It is equivalent to one joule per second (Js-1).
Wave-particle duality
The idea that light is both a wave and a particle.
Wave function
The numerical measure of an electron wave, or in general of the wave corresponding to any quantum mechanical particle.
Wave mechanics
Alternate name for quantum mechanics derived from the wavelike properties of subatomic particles.
Wave motion
The movement of a disturbance produced in one part of a medium to another involving the transfer of energy but not the transfer of matter is called wave motion.
Wave period
The time required for two successive crests of the wave to pass a given point.
Wave velocity
The distance traveled by a wave in one second is called the wave velocity. The wave velocity of a wave depends upon the nature of the medium through which it passes.
Wave
A disturbance or oscillation that moves through a medium.
Wavelength
This is the length of a wave between any two equivalent points. It is easiest to measure from crest to crest or from trough to trough. The SI unit of wavelength is the metre, although kilometres, millimetres, micrometres and nanometres are also used.
Weak nuclear force
The force responsible for beta decay.
Weight
The force with which a body is attracted towards the center of the earth is called its weight. The SI unit of weight is N. The gravitational units of weight are kg-wt and g-wt.
Weightlessness
The state when the apparent weight of a body becomes zero is called the state of weightlessness. All objects while falling freely under the action of gravity appear weightless.
Wind Turbine
A device for converting wind energy into mechanical (windmill) or electrical energy.
Work
When a force acts on a moving object, that force does mechanical work. The work done is defined by the equation:
Work Done = Force x Distance
The SI unit of work is the same as that of energy - the joule.