1.What are the three ways heat energy can be transferred?
"Radiation
2.Which one of these is responsible for heat transfer in a solid?
Conduction
3. Which one of these can only occur in liquids and gases?
Convection
4.Which one of these is often called infrared?
Radiation
5.Do all objects emit heat radiation?
Yes
6.Do all objects absorb heat radiation?
Yes
7. What colour surface is the best emitter of heat radiation?
Black
8. What colour is the best absorber of heat radiation?
Black
9. What surface is the best reflector of heat radiation?
Silver/white
10. In which state of matter are there virtually no forces of attraction between particles?
Gases
11. In which state of matter are there strong forces of attraction between the particles?
Solids
12. What happens to the particles in a solid when they are heated?
They gain kinetic energy and move further apart
13. What is the relationship between density and conduction?
The denser a material the faster the conduction of heat
14. Why are metals such good conductors of heat?
They have free moving electrons (much faster method of heat transfer than vibrating neighbouring particles)
15. Which conducts more efficiently � short thick rods or long thin rods?
Short thick rods
16. What happens to the density of water when it is heated and why?
It decreases because the distance between the particles increases as they have more kinetic energy
17. What happens to the water temperature below the heater element in an immersion heater?
The water stays basically the same temperature
18. How can liquids evaporate below the boiling point of the liquid?
The particles have enough kinetic energy to break free and they are travelling in the right direction
19. Why are car engines black and why do they have �fins�?
Black is the best emitter of heat radiation and the fins increase the surface area for heat loss. (REMEMBER cars break down if the engine overheats!!)
20. Why is there no heat loss by conduction or convection in a vacuum?
A vacuum has no particles both conduction and convection need particles in order to transfer heat.
21. Why do vacuum flasks have plastic stoppers and are usually made of plastic?
Because plastic is an insulator and does not conduct heat very well.
22. What does ear size have to do with heat loss?
The bigger the ear the more heat can be lost by radiation
"23. Which would be more cost effective
double glazing or loft insulation?"
24. What is the relationship between insulation properties and u values?
The better the insulator the lower the u value
25. What is the term used that measures how much energy a substance can store?
The specific heat capacity
26. How is specific heat capacity worked out?
It is the amount of energy needed to raise 1kg of a substance by 1�C
27. Water has a specific heat capacity of 4200J/kg�C and oil has a specific heat capacity of 2000J/kg�C � which would be the best to use in a heating system?
Water
28. What are the nine types of energy?
"Electrical
29. Which of these are forms of stored energy?
"Gravitational potential
30. Can energy be created or destroyed?
No it can only be transferred from one form to another
31. How is the efficiency of a machine/device measured?
The useful energy transferred divided by the total energy supplied
32. What unit is energy measured in?
Joules (J)
33. What unit of energy is power measured in?
Watts (W) or kilowatts (kW)
34. There is only one device that is 100% efficient � what is it?
An electric heater
35. Wasted energy is usually in what form?
Heat
36. Apart from efficiency what other factors should be considered before buying an appliance?
Cost
37. What is a kilowatt-hour (kWh)?
The amount of electrical energy a 1kW appliance uses in a hour.
38. What two formulae are required to work out the cost of electricity?
"Units (kWh) = Power (kW) x Time (hrs)
39. Name four non renewable energy resources.
"Coal
40. Name eight renewable energy resources.
"Wind
41. Name two advantages of wind power.
"No fuel costs
42. Name two disadvantages of wind power.
"Initial costs high/only work in windy conditions
43. Name two advantages of solar cells.
Suitable for use in remote areas/no pollution/free running costs
44. Name two disadvantages of solar cells.
Work better in sunny climates/ high initial costs
45. Name two advantages of hydroelectric power.
Minimal running costs/no pollution
46. Name two disadvantages of hydroelectric power.
Need to flood large areas/ damage habitats/initial costs high
47. Name two advantages of wave power.
No fuel costs/useful for small islands
48. Name two disadvantages of wave power.
Spoil the view/danger to boats/not very reliable/initial costs high
49. Name two advantages of tidal power.
No pollution/no fuel costs
50. Name two disadvantages of tidal power
Spoil the view/problem for boat access/high initial costs
51. Name two advantages of geothermal energy.
No fuel costs/no pollution
52. Name two disadvantages of geothermal energy
Only available near volcanic areas/high initial costs
53. What is a biofuel?
A fuel made from a plant or plant waste
54. What environmental problem is associated with carbon dioxide emissions?
Global warming
55. What environmental problem is associated with sulphur dioxide emissions?
Acid rain
56. What environmental problem is associated with soot and particulates?
Global dimming
57. Why are biofuels often referred to as carbon neutral?
The carbon dioxide they emit when burned equals the carbon dioxide they take in when they are growing
58. Why does the UK not depend too heavily on biofuels?
Because there is insufficient free land available to grow the �fuel crop�.
59. What is CCS?
Carbon capture and storage
60. What could be done with the carbon dioxide produced in power stations?
It could be captured and pumped into empty gas and oil fields.
61. Algae could be used to capture carbon dioxide � what could the algae then be used for?
To produce biofuel
62. How is electricity distributed in the UK?
The National Grid
63. Why is it necessary to increase the voltage and reduce the current when transferring electrical energy?
A high current would mean too much heat would be lost from the electricity cables
64. What is used to increase the voltage?
A step up transformer
65. What is used to decrease the voltage?
A step down transformer
66. How is energy transferred?
By means of waves
67. What is the amplitude of a wave?
The distance between the rest position and the crest.
68. What is the wavelength of a wave?
The distance between two crests
69. What is the frequency of a wave?
The number of waves in a second
70. What is frequency measured in?
Hertz (Hz)
71. Describe a transverse wave?
A wave with sideways vibrations
72. Name two examples of transverse waves.
"Light
73. Describe a longitudinal wave.
A wave with vibrations along the same line.
74. Name two examples of longitudinal waves.
"Sound waves
75. What is the equation to work out the speed of a wave?
Speed (m/s) = frequency (hz) x wavelength (m)
76. Name all the electromagnetic waves in the EM spectrum starting with the one with the longest wavelength.
"Radiowaves
77. Which EM travels the fastest?
TRICK QUESTION � they all travel at the same speed
78. What is the main use of radio waves?
Communication
79. What waves are used in satellite communication?
Microwaves
80. What are the main used of infrared waves?
Optical fibres and wireless remote controllers
81. Optical fibres also use what other type of wave?
Visible light waves
82. What is the relationship between frequency and pitch?
The higher the frequency the higher the pitch
83. What is the relationship between amplitude and loudness?