The nature heat is an energy that cannot be seen, heard, or smelled. However, the influence of this energy can be felt. In addition properties of the heat energy in general also have special properties. This suggests that the heat properties could have moved to another place. The closer the heat source, more hotter and faster it transfered. Further away from the heat source, the less heat is transfer.
Heat transfer from one object to another object occurs when there is a difference in temperature between two objects. heat move from high temperature object to low temperature objects. This movement was continuous until the two objects have the same temperature. For example, if you make a hot tea and pour it into the cup. the tea become more cold, This is because the heat has been transferred from the tea to the cup, and the cup transferred the heat into the environment.
Generally Heat transfer process can be divided into three, namely: conduction (in solids), convection (with liquid), and radiation (without intermediaries).
But You Know??
Ancient scientists have strange ideas about the nature of heat, they take it as a liquid substance which they called heatic. All substances are considered to have heatic a certain amount, depending on how hot. heatic is maintained so that if an object is heated by other things means that the heatic was transferred from a hotter object to cooler object. If this idea is justified by the fact that if the fuel is burned, the weight is reduced. But when scientists tried to determine how much weight change in the substance being burned, but the results are confusing and contradictory. This does not cause them to discard the theory of heatic, they just fix the little theory by stating that "heatic is a weightless liquid substance".
Seventeenth-century physicist Count Rumford , aka Benjamin Thompson, gave a theory which until now accepted as the correct theory of the nature of heat. Rumford observed when drilling a cannon in the late 1790's he noted that the weapon has become hotter after a while once drilled though. He attaching insulation and a box of about nine or ten liters of water that is connected with the barrel of the cannon. When the barrel was drilled, the water becomes hotter in the box, and within two and a half hours it starts to boil. it continues to boil water even after drill become dull so that it can no longer cut. It was obvious that the rotation of the drill in the drilling of cannon transfer heat into the water.
because that experiment Rumford thought, the mechanical energy that is released by rotation of the drill turned into heat, he tried to determine the relationship between the amount of work done by the amount of water to a boil, but the measurement is not careful so it does not acquired definitive results. Later nineteenth-century physicist Sir James Prescott joule, with an improved experimental set with certainty that a certain amount of mechanical energy always produce the same amount of heat. This encouraged the emergence of a new concept of heat as a form of energy and the development of kinetic molecular theory
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