P3

Question 1

Brownian motion

Answer 1

refers to the random movement of particles in a liquid or gas

Question 2

Conduction

Answer 2

Conduction is the transfer of heat from one region to another through particle vibrations and the movement of free electrons

Question 3

Convection

Answer 3

When a liquid (or gas) is heated (for example by a radiator near the floor):
The heated molecules vibrate and push each other apart, making the liquid/gas expand
This makes the hot liquid/gas less dense than the surroundings
The hot liquid/gas rises, and the cooler (surrounding) liquid/gas moves in to take its place
Eventually the hot liquid/gas cools and contracts, increasing in density, and sinks back down again

Question 4

Radiation

Answer 4

Method of radiation which does not require a medium to travel through