The calorie was originally defined as the amount of heat required at a pressure of 1 standard atmosphere to raise the temperature of 1 gram of water 1° Celsius. Since 1925 this calorie has been defined in terms of the joule, the definition since 1948 being that one calorie is equal to approximately 4.2 joules.
What is the relationship between energy and calories?
Calories are the amount of energy released when your body breaks down (digests and absorbs) food. The more calories a food has, the more energy it can provide to your body. When you eat more calories than you need, your body stores the extra calories as body fat. Even a fat-free food can have a lot of calories.
What is the relationship between a KiloJoule and a joule?
Joules and KiloJoules are units of the international system of units (SI) that measure energy. The standard symbol for Joule is J, whereas the symbol for KiloJoule is KJ. 1 J equals precisely 0.001 KJ, therefore there are 1,000 Joules in a KiloJoule.
Which is bigger calorie or joule?
The unit joule is defined in terms of work done. However, the calorie is defined in terms of the heat energy as follows: One calorie is the amount of heat required to raise the temperature of a one gram of water by one degree Celsius. Hence, we see here that the calorie is numerically, greater than the joule.
What is the relationship between a calorie and a kilocalorie which unit is larger?
To ease calculations, energy is expressed in 1000-calorie units known as kilocalories. That is, 1 Calorie is equivalent to 1 kilocalorie