The joule is the SI unit of energy and is equal to 1 kg m² s⁻². The erg is another energy unit, equal to 1 g cm² s⁻². Use unit conversion methods to work out how many ergs are in 1 joule. A)10 ⁻¹ ergs B)10 ergs C)10 ² ergs D)10 ⁵ ergs E)10 ⁷ ergs

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Quizplus · Accepted Answer

1 joule is equal to $1 \, \text{kg} \cdot \text{m}^2 \cdot \text{s}^{-2}$, and 1 erg is equal to $1 \, \text{g} \cdot \text{cm}^2 \cdot \text{s}^{-2}$. Converting kilograms to grams and meters to centimeters, 1 kg = $10^3$ g and 1 m = $10^2$ cm, so $1 \, \text{kg} \cdot \text{m}^2 = 10^3 \, \text{g} \cdot (10^2)^2 \, \text{cm}^2 = 10^7 \, \text{g} \cdot \text{cm}^2$. Therefore, 1 joule = $10^7$ ergs.

The Joule Is the SI Unit of Energy and Is