The Definition of a Calorie!

A calorie is defined as the amount of energy it takes to raise 1 gram of water (which is about 1 cubic centimeter -- about a thimble full) 1 degrees Celsius.

Calories you hear about in food are actually kilocalories (1000 calories). So if a twinkie has 300 food calories, it could raise 300 kilograms of water 1 degrees celsius (that's impressive!).
That much energy could also raise the body temperature of a 60 kilogram person 5 degrees celsius.

Power is energy use (conversion, actually) over time. You are probably most familiar with watts as the unit of measure for power -- like a 100 watt light bulb.
A watt is defined as a "Joule per second." To convert from calories to Joules, you multiply by 4.1868.


QUESTION: If all the energy from a 100 Watt light bulb were put into 1 gram of water (at room temperature) for 1 second, how much would the temperature increase?

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