Wh vers erg convertisseur - Watt-heure vers Erg

Conversion derivation

Express both Wh and erg in the same base unit J (joule), then cancel the shared base unit.

1. 1

   Rewrite Wh in the base unit

   $$1\mathrm{Wh}=3,600\mathrm{J}$$
2. 2

   Rewrite erg in the base unit

   $$1\mathrm{erg}=1\times 10^{-7}\mathrm{J}$$
3. 3

   Forward conversion

   $$\begin{array}{rl}1\mathrm{Wh}& =\frac{3,600\cancel{\mathrm{J}}}{1\times 10^{-7}\cancel{\mathrm{J}}}\times 1\mathrm{erg}\\ & =\frac{3,600}{1\times 10^{-7}}\mathrm{erg}\\ & =3.6\times 10^{10}\mathrm{erg}\end{array}$$
4. 4

   Reverse conversion

   $$\begin{array}{rl}1\mathrm{erg}& =\frac{1\times 10^{-7}\cancel{\mathrm{J}}}{3,600\cancel{\mathrm{J}}}\times 1\mathrm{Wh}\\ & =\frac{1\times 10^{-7}}{3,600}\mathrm{Wh}\\ & =2.77777778\times 10^{-11}\mathrm{Wh}\end{array}$$