All cooking methods use one or more methods of heat transfer in order to cook the food.
The three methods of heat transfer are as follows:
Using a toaster and grilling food are good examples of using radiation to transfer heat. When heat is radiated it travels in straight lines and any object in its path becomes heated.
Heating a pan on a hob is a good illustration of conduction. In this method, heat travels through a solid, e.g. the pan. Metal objects are good conductors of heat and so these are used in the making of saucepans. Cotton is a less effective heat conductor and hence it is used in the production of oven-gloves.
A gas oven or cooking in boiling water are good illustrations of heat being transferred by convection. When heated, the particles of a liquid (e.g. water) or a gas (e.g. air) become lighter and rise, while colder particles sink to the bottom and are then heated in turn
Heat in practice
The face is hot because of Radiant Heat
The Spoon handle will become hot due to Conducted Heat even though it is not in the water
The water in the pan will become hot because of the radiant heat from the gas flame will be conducted through the base of the pan and the Convected Heat will make the water warm
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