Wave
Front
The wave front of a wave is a surface at
each point of which the vibrating particles are in same phase.
Wave
Length
Distance travelled by the wave in the time
in which particle of medium completes one vibration.
or
Distance between two nearest particles in the
same phase.
Wave
Motion
It is a form of
disturbance which travels through the medium due to repeated periodic motion of
particles of medium about their mean positions. Wave motion, in general, refers
to transfer of energy from one point to another point of medium. It is not
matter that is propagated but it is only state motion of matter that is propagated.
It is a form of dynamic condition that is propagated from one point to the
other point in the medium.
Wave
Wave is pattern
and doesn’t have any physical existence. Wave motion comprises of patterns
repeating at regular intervals and thus wave travels with uniform velocity.
Weidmann-Franz
Law
The linear dependence of “ratio of thermal
conductivity to electrical conductivity” on absolute temperature is known as
Weidmann-Franz law. The ratio is directly proportional to absolute temperature.
Weight
Percent (wt%)
Weight of a
particular element relative to the total alloy weight.
Weld
Decay
Intergranular
corrosion that occurs in some welded stainless steels at regions adjacent to
the weld.
Welding
Process of permanently joining two similar
metals by localized fusion by applying suitable heat and pressure is called as
welding.
Wet
Bulb Temperature
Wet-bulb
temperature represents how much moisture the air can evaporate. This
temperature is often measured with a common mercury thermometer that has the
bulb covered with a water-moistened wick and with a known air velocity passing
over the wick.
White
Dwarf
They are stars
which are fainter, possess small diameter, and are very dense compared to other
stars of same mass. A white dwarf star is a mass of Helium at an extremely high
temperature and under external compression. At its central temperature, Helium
atoms are expected to be completely ionized and the star may be regarded as gas
composed of Helium nuclei and electrons.
Wiedmann
Franz Law
The
ratio of thermal conductivity(K) to electrical conductivity σ is a constant
(called Lorentz number) at a particular temperature for all the metals.
or
Weidmann–Franz
discovered in 1853 that all good electrical conductors are also good thermal
conductors. Ratio of K to σ is constant at a particular
temperature for all the metals. Later Lorentz showed that this ratio is
proportional to absolute temperature ‘T’.
K/σT= const=L; L is called as Lorentz number.
Wien’s
Displacement Law
The
wavelength of radiation emitted by a black body at any temperature is inversely
proportional to absolute temperature of the body.
or
At
any temperature, the energy of radiations of wavelength emitted by black body
is directly proportional to fifth power of its absolute temperature.
Work
If the applied
force on object leads to some displacement then it is said that work is done on
object.
Work-Energy
Theorem
The work done by the resultant net force
acting on a body is equal to change in its kinetic energy.
Wrought
Alloy
A metal alloy that is relatively ductile
and amenable to hot working or cold working during fabrication.