Ch.10 lesson 3: The Transfer Of Heat

Key Idea: How Is Heat Transferred?

Heat is transferred from warmer areas to cooler areas by means of conduction, convection, and radiation.

Radiation

Radiation is a form of heat transfer in which heat "radiates" or spreads out from one object to another. This occurs when heat travels from the sun to the earth.

What form of heat transfer occurs when heat from the sun warms a sidewalk?

Radiation occurs when the heat from the sun hits a sidewalk, because the heat has separated from the sun and has traveled to the sidewalk, therefore warming it.

What type of heat transfer occurs in a boiling pot?

All three, because as the pot is being warmed by the stove (conduction), convection occurs in the water as heat rises and cools, than falls back down. The heat conducted by this causes heat to radiate from the pot, therefore causing radiation.

Conduction

Conduction is a form of heat transfer in which heat travels from one object to another. Such as when you touch a hot stove.

Say you touch a hot stove and burn your finger. What form of heat transfer has just occurred?

Conduction occurs when you put your finger to a hot stove because heat from the stove is transferred to your finger by touch.

Convection

Convection is a form of heat transfer in which hot air/ liquid rises and cools while cool air/ liquid falls and warms. For example, the air in the atmosphere is constantly cycling due to the hot sun, and the cool ground.

Convection Current

The circular motion of air/ liquid caused by convection. The cycling air in the atmosphere is also a great example of this.