Heat Transfer Conduction, Convection, Radiation. Three Main Processes of Heat Transfer  Conduction  Convection  Radiation.

Presentation on theme: "Heat Transfer Conduction, Convection, Radiation. Three Main Processes of Heat Transfer  Conduction  Convection  Radiation."— Presentation transcript:

Three Main Processes of Heat Transfer  Conduction  Convection  Radiation

Conduction  Transfer of heat between substances or objects that are in direct contact with each other.  Heat travels from object at higher temperature to object at lower temperature.  If it feels hot, the heat is transferring into you from the object.  If it feels cold, then heat is transferring from you into the object.  Heat is transferred from the faster moving particles to the slower moving particles by colliding. This continues until both objects have reached the same temperature, thermal equilibrium.

Conduction  Conduction occurs in all states of matter, but works best in solids since the particles are closer together.  Metals are especially good conductors of heat.

Convection  Heat transfers through the motion of a fluid.  The hotter fluids rise and the cooler fluids fall due to the difference in densities.  Occurs in a gas, liquid, or plasma  The rising and falling motion of the fluid is called a convection current.

Radiation  The transfer of heat through electromagnetic waves.  Electromagnetic waves carry a certain amount of energy that is directly proportional to the frequency of the wave.  Lower frequency waves have less energy, and higher frequency waves have more energy  The main source of heat through radiation of Earth is the Sun.  The heat is transferred to the molecules in the air, water, and land.  The greenhouse effect occurs when the Earth’s atmosphere absorbs and traps thermal radiation from the Earth’s surface.  This can also be seen on a smaller scale with a greenhouse or a Crookes radiometer.

Page 260 in the book  You need to transfer the chart and the picture of the fire into your journal.  The picture needs to be labeled exactly as you see it.