DISCOVER

# Examples of Conduction in the Home

Conduction represents the most direct form of energy transfer between two objects because it requires the objects to be in physical contact. Two other, less direct forms of heat transference exist as well, known as convection and radiation. Both of these types depend on particles travelling through the air or heated air itself to transfer energy, while conduction allows heat to flow directly and more efficiently between two objects.

## Kitchen Conduction

When a skillet sits on a hot stove, conduction acts to heat it, transferring the energy of the hob into the skillet. Similarly, bacon placed in the hot skillet will absorb heat directly from the skillet until it is hot enough to cook. A ceramic coffee cup filled with hot tea or coffee also exhibits conduction, which transfers the heat of the liquid into the material of the cup. Even burning your finger by touching the stove before it cools down constitutes conduction: so much heat is transferred to your finger in a direct manner that your skin cannot conduct the heat away from the hot skin fast enough to prevent damage to your nerve endings.

## Hot Water Heaters

A hot water heater operates by immersing a heating element in water and allowing conduction to heat the water to a desired temperature. When you turn on the tap, water rushes out until the hot water has pushed out any cooler water in the pipe. Gripping the faucet with your palm, you can feel it getting warmer as conduction pulls heat energy out of the water and into the material of the faucet (and then to your hand).

## Walls and Floors

Hyperphysics, the website of the Georgia State University Physics department, explains how conduction accounts for heat acquired and lost in the home and how that conduction affects the cost of heating and cooling. Uninsulated walls and floors are responsible for a lot of heat loss in the winter, as demonstrated by the walls or floor feeling cold to the touch. To test this yourself, place one thermometer hear the area being tested and hang another one from the ceiling so that it is suspended in the centre of the room. The area near the test site will be cooler in the winter and warmer in the summer, reflecting the amount of heat energy conducted through the surface.