An erg is a unit for energy:

[math]\textrm{1 erg} = 1 \frac{\textrm{g} \cdot \textrm{cm}^2}{\textrm{s}^2}[/math]

This can be shown to be equal to exactly 10-7 joules:

[math] \frac{\textrm{1 g} \times \textrm{1 cm}^2}{\textrm{1 s}^2}\times \frac{\textrm{1 kg}}{\textrm{1000 g}} \times \frac{\textrm{1 m}^2}{\textrm{10000 cm}^2}=10^{-7}\textrm{ J} [/math]

The erg is a miniscule amount of energy, often compared to the work it takes for a mosquito to take off.[1]


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