➽ ENERGY - Energy and temperature

Question 1

What is temperature?

Answer 1

Temperature is how hot or cold something is.

Question 2

What is temperature measured in?

Answer 2

Degrees Celsius (°C).

Question 3

How can we measure temperature?

Answer 3

Using a thermometer.

Question 4

Why can’t we measure temperature using our touch?

Answer 4

Regardless of the actual temperature, if something is hotter than our skin, then it’ll feel warm, and if something is colder than our skin, it’ll feel cold.

Question 5

How do thermometers work?

Answer 5

1. Digital thermometers - use sensors
2. Glass thermometers contain a liquid which expands when the temperature increases.

Question 6

What two things determine how much thermal energy an object contains?

Answer 6

1. The temperature of the object
2. The mass of the object

Question 7

How do objects heat up when heated?

Answer 7

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 the object to heat up.

Question 8

What determines how much energy is needed to heat an object?

Answer 8

1. Mass of the object
2. Material of the object
3. Desired temperature increase.

Question 9

How does the mass of an object determine how much energy is needed to heat an object?

Answer 9

The larger the mass, the more particles in the object so more energy needs to be transferred to heat the entire object.

Question 10

How does the material of an object determine how much energy is needed to heat an object?

Answer 10

Material can depend on many things:
1. Density
2. Colour
3. Shiny or matt

Question 11

How does the density of an object determine how much energy is needed to heat an object?

Answer 11

The denser an object is, the closer its particles are, so less energy is needed to make the particles collide, allowing the object to be heated more quickly and using less energy.

Question 12

What does equilibrium mean in terms of temperature?

Answer 12

1. If an object is in equilibrium, then all the particles have the same amount of energy, and the entire object is at the same temperature.
2. If two objects are in equilibrium, then they are at the same temperature.

Question 13

How does energy naturally flow?

Answer 13

From hot to cold, until both objects/areas are at the same temperature.