# [2013] Matthew Brown: Conduction, Convection, Radiation

In Glogpedia

by mikeeby
Last updated 5 years ago

Discipline:
Science
Subject:
Physics
8

Conduction is the transfer of heat energy through a material (The material is the medium, or the intervening substance). When the objects touch, their particles collide. Heat energy moves from the hotter object to the cooler object.

*An example of radiation is to the left of this text box. The radiation given off from the fire is felt by the person's hands, and this absorbed radiation turns into heat that is felt by the person.*A well-know example of radiation is the Sun. The sun gives off radiation across empty space. The sun gives off radiation which all living things absorb, which is what we feel as heat from the sun.

Convection is the transfer of heat energy through a gas or a liquid. As a gas or liquid heats up, it rises and becomes less dense. As it rises, it gets further away from its heat source. The gas or liquid would soon cool down, becoming more dense and falling back to its heat source, thus creating a cycle of a hot and cold gas/liquid. This cycle creates convection currents, currents that result from convection. The above example of friction creates convection curents.

*An example of conduction is above. The candle is hotter than the stick held over it. When the stick is held over the candle, the heat is transferred from the candle to the stick, making the stick hot.*However, conduction is not just between objects that widely range in temperature. Conduction can occur between objects are -10 degrees Fahrenheit and -5 degrees Fahrenheit. The second object is "hotter," in a sense, than the first object, so there is still a heat transfer.

What is Conduction?

Examples of Conduction

What is Convection?

Examples of Convection

*An example of convection is above. The heat under the kettle is the heat source. The water gets warmer from the heat and rises. It quickly cools and falls back to its heat source, repeating the cycle of convection.* Another occurring example of convection is in the wind. Warm air rises from the ground then sinks on the surface of water, creating a sea breeze; however, a land breeze is a bit different. Instead of the land warming up, the sea warms up. Warm air rises from the sea then cools, falling on the surface of the land, creating a land breeze.

Radiation is the transfer of heat through electromagnetic waves. The ernrgy can transfer between particles of matter or across empty space.