Calorie (cal) or small calorie, is the amount of energy needed to heat one gram of water by one degree Celsius.
One small calorie is approximately 4.2 joules.
A calorie is a unit of energy.
For example:
Q = 150000 J; released energy.
Convert Jules in calories:
Q = 150000 J ÷ 4.186 J/calorie.
Q = 35833.73 calorie.
The large calorie or nutritional calorie (symbols: Cal, kcal) is the heat energy needed to raise the temperature of one kilogramof water by one degree Celsius.
A nutritional calorie, or kilocalorie, is equal to 1000 calories.
One large calorie is 4.184 kilojoules: 1 Cal = 4.184 kJ.
For example:
E = 2500 Cal; energy burnt.
E = 2500 Cal · 4.184 kJ/Cal.
E = 10460 kJ.
