➽ ENERGY - Energy transfer: particles

Question 1

What are conductors?

Answer 1

Objects that allow for the easy flow of energy.

Question 2

What types of material is a good conductor?

Answer 2

Metals

Question 3

In which state the conduction usually take place?

Answer 3

Solids

Question 4

Which states are considered insulators?

Answer 4

Liquids and gases

Question 5

Why are solids better conductors then liquids and gases?

Answer 5

The particles are closer together and so can easily collide with neighbouring particles to pass on energy.

Question 6

Why are liquids and gases good insulators?

Answer 6

Their particles are far apart so it takes longer and more energy for them to collide and transfer energy across.

Question 7

Name 3 ways energy can be tranferred.

Answer 7

1. Conduction
2. Convection
3. Radiation

Question 8

How does conduction occur?

Answer 8

1. Energy stored in the chemical energy store of the fuel is transferred to the kinetic energy store of the particles.
2. More kinetic energy means the particles move faster and with more energy.
3. This causes the particles to collide more frequently and with greater force with their surrounding particles.
4. Each collision releases thermal energy to the particles and the surroundings.
5. This causes energy to be transferred to neighbouring particles
6. This continues until the object is in equilibrium.

Question 9

What type of solids are good insulators?

Answer 9

Non-metals

Question 10

What are insulators?

Answer 10

Objects that limit energy transfer, poor conductors.

Question 11

Give an example of how liquid can act as an insulator.

Answer 11

Diver wetsuits trap a layer of water to insulate and keep divers warm.

Question 12

Give an example of how gas can act as an insulator.

Answer 12

Trapped air (e.g., in duvets) insulates by preventing heat transfer.

Question 13

In which state does convection take place?

Answer 13

Liquids and gases

Question 14

How does convection take place?

Answer 14

1. The particles close to the heat source gain energy.
2. This causes them to become further apart.
3. This causes that part of the air/liquid to become less dense.
4. Cooler, denser liquid/air sinks
5. The cooler, denser liquid/air then heats up and becomes less dense.
6. This cycle repeats and is called a convection current.

Question 15

What effect does sound have on the temperature of the environment?

Answer 15

Loud sounds can cause an increase in temperature.

Question 16

How can sounds contribute to temperature increase?

Answer 16

Sounds are longitudinal waves, carrying energy, and when particles collide with each other or objects in the room, e.g. a wall, then a little thermal energy is released.