Energy+icsDinh18

paragraph about heat transfer:

There are three types of heat transfer: conduction, convection, and radiation. Conduction heat transfer refers to two surfaces touching each other, example a metal pan on the stove, when the handle is touched; your hand begins to feel hot. Convection heat transfer in liquids and gases, convection currents are set up in the fluid because the hotter part of the fluid is not as dense as the cooler part, so the hotter fluid rises while the cooler is below. Radiation heat transfer that does not rely any contact between the sources and object as is the case with conduction and convection. Heat can be transmitted through empty space by thermal radiation; example of radiation is the heat from the sun, the heat released from the light bulb, or from space heater.