kcal vers MJ convertisseur - Kilocalorie vers Megajoule

Conversion derivation

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

1. 1

   Rewrite kcal in the base unit

   $$1\mathrm{kcal}=4,184\mathrm{J}$$
2. 2

   Rewrite MJ in the base unit

   $$1\mathrm{MJ}=1,000,000\mathrm{J}$$
3. 3

   Forward conversion

   $$\begin{array}{rl}1\mathrm{kcal}& =\frac{4,184\cancel{\mathrm{J}}}{1,000,000\cancel{\mathrm{J}}}\times 1\mathrm{MJ}\\ & =\frac{4,184}{1,000,000}\mathrm{MJ}\\ & =0.004184\mathrm{MJ}\end{array}$$
4. 4

   Reverse conversion

   $$\begin{array}{rl}1\mathrm{MJ}& =\frac{1,000,000\cancel{\mathrm{J}}}{4,184\cancel{\mathrm{J}}}\times 1\mathrm{kcal}\\ & =\frac{1,000,000}{4,184}\mathrm{kcal}\\ & =239.005736138\mathrm{kcal}\end{array}$$