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How to Convert eV/THZ to Joule Seconds

Dealing with electricity sometimes requires the conversion from one set of units to another system of units depending on who uses them. Chemists, physicists and engineers all use different units when talking about energy, in particular photon energy. Converting energy between units of joules and electron volts (eV) is achieved by multiplying the energy in eV by the charge on an electron (1.602 x 10^-19 C). Frequency relates to the energy of a photon through the formula, E = h * freq., where h is Planck's constant (6.626 x 10^-34 Jsec). 1 eV equals 1.602 x 10^-19 J.

Instructions

- 1
  Learn the numeric values of the metric system of measurements. It is important for any type of technical manipulations or calculations with numbers that you know what the various prefixes to the units mean. For example, a kilometer is 1,000 meters, M bits represents 10^6 bits of information and GHz stands for 10^9 Hz. THz equals 10^12 Hz.
- 2
  Convert the number of eV to Joules. To determine the number of joules, multiply the number of eV by the charge on an electron. The charge on an electron is 1.602 x 10^-19 C. Use the example of converting 5.3 eV to joules. E(J) = E(eV) * e(C) = 5.3 eV * (1.602 x 10^-19 C) = 5.3 * 1.602 * 10^-19 = 8.49 x 10^-19 J.
- 3
  Convert THz to sec^-1. Use the definition T in the metric system to express THz. T equals 10^12, therefore THz = 10^12 Hz. 1 Hz equals 1 / seconds. For example, 1 THz = 10^12 Hz = 10^12 sec^-1.
- 4
  Combine these two conversions and find the number of Joule seconds from eV / THz. Finishing the example, eV / THz = eV * e / 10^12 Hz = 5.3 * 1.602 X 10^-19 / 10^12 seconds^-1 = 8.49 x 10^-19 J / 10^12 seconds^-1 = 8.49 x 10^-32 Joules seconds.

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