Heat Transfer

Question 1

What solid materials are good conductors of thermal energy and why

Answer 1

Metals as they have free electrons which can move about, transferring heat

Question 2

Why are other solid materials not great conductors of heat

Answer 2

Their electrons aren’t free and only vibrate to transfer heat

Question 3

What are the 4 methods of heat transfer?

Answer 3

Conduction, convection, evaporation, radiation

Question 4

What is conduction?

Answer 4

The thermal transfer of energy between neighbouring atoms

Question 5

Explain the process of conduction

Answer 5

When atoms gain energy, they begin to vibrate more. When one atom collides with another, some of this energy is transferred to the other atom.

Question 6

Why can conduction not happen in a vacuum?

Answer 6

Because there are no particles for the heat to transfer to

Question 7

What is convection?

Answer 7

A process where the thermal energy is transferred through the movement of particles. It can only occur in liquids and gases because in solids the particles aren’t free to move.

Question 8

Describe the process of convection

Answer 8

A fluid is heated, temp of fluid goes up, particles vibrate more. Particles move further apart, decreased density of fluid. Warmer fluid rises as it’s less dense than surroundings. Replaced by colder fluid underneath which is then heated. Warmer fluid at top cools, density increases, sinks- convection current