physics heat energy

6

what is a conductor

• a material that allows internal (thermal) energy to be transmitted through it easily.

why are all metals good conductors?

• when one end of a metal rod is put into a fire, the energy from the flame makes the ions in the rod vibrate faster.

• since the ions in the solid metal are close together, this increased vibration means that they collide with neighbouring ions more frequently.

• energy is passed on through the metal by these collisions, transmitting the energy.

• more frequent collisions increase the rate of transfer.

whats an insulator?

• a material that will not allow the easy flow of energy.

how do you compare conductivities?

metals conductivities can be compared by examining the time taken to transmit energy through them.

the rod that gets hottest first at the other end is the best conductor.

what happens when materials are heated?

• when materials are heated, the molecules gain kinetic energy and start moving faster.

• the result is that the material gets hotter.