J → kcal
James Joule discovered the relationship between heat and mechanical work in the 1840s, establishing the law of energy conservation.
Einstein's E=mc² revealed that a tiny amount of mass contains enormous energy. One gram of matter equals 90 trillion joules!
Ancient Greeks used "water organs" (hydraulis) around 250 BCE, early understanding of converting water energy to sound.
The Large Hadron Collider uses 14 teraelectronvolts (TeV) of energy to smash particles together, recreating conditions from the Big Bang.
Why did the joule go to school? To get more potential energy! ⚡