# P1a

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1. What is temperature?
Measure of how hot something is using a scale. It is also a measurement of the average kinetic energy of the particles.
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2. What are the units of temperature?
Degrees Celsius.
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3. What is it called when temperature is represented by colours?
A thermogram.
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4. What do the hot areas show in thermograms?
White/Yellow/Red
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5. What do the cold areas show in thermograms?
Black/Dark blue/Purple
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6. What is heat?
A measurement of energy and is measured in Joules. Absolute scale.
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7. If an objects temperture rises, it is...
taking in heat energy from its surroundings.
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8. If an objects temperature falls, it is...
giving out heat energy to its surroundings.
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9. Will a object with very high temperatures cool down quicker or slower than a less hot object?
Faster.
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10. What does the graph of a cup of tea look like when it is cooling down?
Decreasing at a decreasing rate.
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11. What does the amount of energy needed to raise the temperature of an object depend on?
Mass, the change in temperature required and the material its made from.
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12. What is the equation for Total Energy Supplied?
Total energy supplied = energy supplied per second x number of seconds
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13. What is the electric heater known when experimenting for heat energy?
Heat source.
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14. And what is the aluminium block called?
Heat sink.
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15. What is the Specific Heat Capacity?
How much energy it can hold. It is also the energy needed to increase the temperature of 1kg of material by 1 degree celsius.
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16. What is the equation for energy? (include SHC)
Energy = mass (kg) x SHC (J/kgdegree) x temperature change
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17. Why doesn't the temperature of a substance change when it changes state?
All energy is going into changing the state not the temperature.
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18. What is happening during the melting and boiling of water?
The intermolecular bonds are being broken.
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19. Can the temperature of water ever rise above 100degrees?
No, but steam produced can.
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20. What is the Specfic Latent Heat of a material?
It is the amount of heat energy required to melt or boil 1kg of material.
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21. What does the SLH depend on?
The material and the state (solid, liquid or gas)
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22. What is the equation for energy (using SLH)?
Energy = Mass (kg) x Specific Latent Heat
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23. What are conductors?
Materials that allow energy to flow through them.
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24. What are insulators?
Materials that allow energy to flow through them more slowly.
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25. Give an example of an conductor.
Most metals
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26. Give an example of a insulator.
Wood, plastic, glass or air. Most non-metals.
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27. Why are curtains good insulators?
They have a layer of air between them and the window. Air is a good insulator because the particles are really far apart.
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28. What does fibreglass insulation reduce and how?
Conduction and Convection. Trapping air between fibres.
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29. What does reflective foil reduce and how?
Radiation. Reflecting heat energy back into the room.
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30. What does foam cavity wall insulation reduce and how?
Conduction and Convection. Traps air into the foam.
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31. What does double glazing reduce and how?
Conduction and Convection. Trapping air between glass.
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32. What do draught excluders reduce and how?
Conduction and Convection. Reduce the dissapearence of warm air.
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33. What is the calculation for payback time?
Payback time = Initial cost/annual saving.
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34. How does cavity wall insulation work?
Made up of an inner and outer wall separated by air. Heat energy gets into the air and warms it. This can be reduced by filling cavitiy with foam, heat loss is reduced.
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35. What is energy efficiency?
How could an appliance is at converting input energy into useful output energy.
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36. What is the equation for efficiency?
Useful output energy/total input energy
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27. What is a sankey diagram?
Shows energy efficiency.
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38. What are some examples of how heat transfers are reduced in everyday life
Kettles made from shiney surfaces to reduce radiation. Hot-water tanks are also made from shiny surfaces to reduce radiation, they also have an insulating jacket to reduce convection and conduction.
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39. What is conduction?
Transfer of heat energy through a substance from a hotter to a cooler region.
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40. What happens during conduction?
The kinetic energy of particles increases. This energy is passed between particles and energy is transferred. It can conduct heat because of free electrons which can carry energy.
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41. What is convection?
Transfer of heat energy from hotter to cooler region by movement of particles.
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42. What happens during convection?
As a liquid gets hotter, its particles move faster, this expands and becomes less dense. These particles rise up and are replaced by particles from the cooler, denser region.
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Hot objects emit infra-red radiation, an electromagnetic wave. This can pass through a vacuum.
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44. Compare dark matt surfaces to light shiny surfaces.
Dark matt surfaces emit and absorb more radiation to light shiny surfaces at the same temperature. However dark matt surfaces are poorer reflectors.
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## Other cards in this set

### Card 2

#### Front

2. What are the units of temperature?

Degrees Celsius.

### Card 3

#### Front

3. What is it called when temperature is represented by colours?

### Card 4

#### Front

4. What do the hot areas show in thermograms?

### Card 5

#### Front

5. What do the cold areas show in thermograms?