Energy Conversions - Maple Help

Conversion between Energy Units

Description

 • In certain fields, for example, chemistry and physics, it is often useful to convert between various energy units.  Common examples are the conversions among frequency (MHz), wavenumber (1/cm), energy (hartrees), molar energy (kJ/mol), and temperature (kelvin).
 • Energy conversions are performed by using the 'energy'=true option with the functions convert/units and convert/dimensions.
 • Energy conversions may be seen as applying the following transformations on the dimensions of the units:

 1 second = c meters 1 kilogram = c/h per meter 1 kelvin = k/(h*c) per meter 1 ampere = 1/sqrt(1e7*c*h) per meter 1 candela = 1/(683*c^2*h) per square meter steradian

 where c is the absolute value of the speed of light in meters per second, by definition $299792458$, h is the absolute value of the Planck constant in joule seconds, approximately $6.6260755×{10}^{-34}$, and k is the absolute value of the Boltzmann constant in joules per kelvin, approximately $1.380658×{10}^{-23}$.

Examples

Convert the wavenumber to frequency, energy, molar energy, and temperature.

 > $\mathrm{convert}\left(\frac{1}{'\mathrm{centimeter}'},'\mathrm{dimensions}','\mathrm{energy}'=\mathrm{true}\right)$
 $\frac{{1}}{{\mathrm{length}}}$ (1)
 > $\mathrm{convert}\left(83.59347279,'\mathrm{units}',\frac{1}{'\mathrm{centimeter}'},'\mathrm{megahertz}','\mathrm{energy}'=\mathrm{true}\right)$
 ${2.506069268}{×}{{10}}^{{6}}$ (2)
 > $\mathrm{convert}\left(83.59347279,'\mathrm{units}',\frac{1}{'\mathrm{centimeter}'},'\mathrm{attojoules}','\mathrm{energy}'=\mathrm{true}\right)$
 ${0.001660539049}$ (3)
 > $\mathrm{convert}\left(83.59347279,'\mathrm{units}',\frac{1}{'\mathrm{centimeter}'},\frac{'\mathrm{kilojoules}'}{'\mathrm{mole}'},'\mathrm{energy}'=\mathrm{true}\right)$
 ${1.000000006}$ (4)
 > $\mathrm{convert}\left(83.59347279,'\mathrm{units}',\frac{1}{'\mathrm{centimeter}'},'\mathrm{kelvin}','\mathrm{energy}'=\mathrm{true}\right)$
 ${120.2723964}$ (5)

Convert the SI unit coulombs to its associated units in the CGS electromagnetic (EMU) and electrostatic (ESU) systems.

 > $\mathrm{convert}\left('C','\mathrm{dimensions}','\mathrm{energy}'=\mathrm{true}\right)$
 ${1}$ (6)
 > $\mathrm{convert}\left(1.6021917×{10}^{-19},'\mathrm{units}','C',\mathrm{sqrt}\left('\mathrm{centimeters}''\mathrm{gram}'\right),'\mathrm{energy}'=\mathrm{true}\right)$
 ${1.602191700}{×}{{10}}^{{-20}}$ (7)
 > $\mathrm{convert}\left(1.6021917×{10}^{-19},'\mathrm{units}','C',\frac{{'\mathrm{centimeters}'}^{\frac{3}{2}}{'\mathrm{gram}'}^{\frac{1}{2}}}{'\mathrm{second}'},'\mathrm{energy}'=\mathrm{true}\right)$
 ${4.803249879}{×}{{10}}^{{-10}}$ (8)

Convert the speed of light into units of action (1 planck = 1 joule second).

 > $\mathrm{convert}\left(\frac{'m'}{'s'},'\mathrm{dimensions}','\mathrm{energy}'=\mathrm{true}\right)$
 ${1}$ (9)
 > $\mathrm{convert}\left(2.99792458×{10}^{8},'\mathrm{units}',\frac{'m'}{'s'},'\mathrm{planck}','\mathrm{energy}'=\mathrm{true}\right)$
 ${6.626070041}{×}{{10}}^{{-34}}$ (10)

 > $\mathrm{convert}\left('W','\mathrm{dimensions}','\mathrm{energy}'=\mathrm{true}\right)$
 $\frac{{1}}{{{\mathrm{length}}}^{{2}}}$ (11)
 > $\mathrm{convert}\left(299.7924580,'\mathrm{units}','\mathrm{newtons}','\mathrm{watts}','\mathrm{energy}'=\mathrm{true}\right)$
 ${8.987551787}{×}{{10}}^{{10}}$ (12)
 > $\mathrm{convert}\left(299.7924580,'\mathrm{units}','\mathrm{joule}',\mathrm{sqrt}\left('\mathrm{watts}'\right),'\mathrm{energy}'=\mathrm{true}\right)$
 ${1.164642654}{×}{{10}}^{{19}}$ (13)