P2

Question 1

What’s the process of conduction?

Answer 1

Heat is transferred to the kinetic energy store of the particles which causes them to vibrate faster, so energy is transferred to neighbour particles.

Question 2

What does thermal conductivity mean?

Answer 2

How well objects transfer energy by conduction.

Question 3

What process commonly transfers heat through the following mediums:
a) solids
b) fluids
c) empty space

Answer 3

a) conduction
b) convection
c) radiation

Question 4

Why does conduction mainly occur in solids but rarely in liquids and gases?

Answer 4

Because the particles in a solid are held very closely which means many collisions happen that pass on energy, but in liquids and gases particles are further apart so they don’t collide as much.

Question 5

Give an example of a material with a low thermal conductivity

Answer 5

Plastic

Question 6

Describe the process of convection in a container of fluid.

Answer 6

As it’s heated, the particles near the heat will gain kinetic energy and spread out, meaning they are less dense. This means they rise above the denser particles and the cooler ones take their place. The hot particles will lose their energy and cool down. And the cooler ones will heat up and repeat the whole process.

Question 7

What is one similarity and one difference between convection?

Answer 7

Similarity: Both involve particles gaining kinetic energy
Difference: In conduction only energy is transferred in convection the particles move.

Question 8

What kind of heat transfer doesn’t require particles?

Answer 8

Radiation

Question 9

What’s the process of radiation?

Answer 10

How is energy transferred? How can we reduce the method of energy transfer?
Radiation Energy is transferred by an electromagnetic wave. Use shiny white or silver surfaces.
Conduction Particles collide with each other. Conduction can occur between objects if they are touching. Use insulators.
Convection Hotter fluid is less dense than colder fluid so it rises. Energy is transferred by the moving fluid. Stop the fluid f

Answer 11

How is energy transferred? How can we reduce the method of energy transfer?
Radiation Energy is transferred by an electromagnetic wave. Use shiny white or silver surfaces.
Conduction Particles collide with each other. Conduction can occur between objects if they are touching. Use insulators.
Convection Hotter fluid is less dense than colder fluid so it rises. Energy is transferred by the moving fluid. Stop the fluid f