What is a Joule?
A Joule (J) is the standard unit of energy in the metric system. It's roughly the amount of energy required to lift a small apple one meter straight up.
Calories (The Energy in Food)
When you see "Calories" on a food label, it's actually kilocalories (kcal).
- 1 kcal = 4,184 Joules
Kilowatt-Hours (kWh)
This is how your power company measures your energy usage. It's the energy used by a 1,000-watt appliance running for one hour.
- 1 kWh = 3,600,000 Joules
Key Takeaways
- Calories measure heat energy
- kWh measures electrical energy
- Joules are the base unit for everything