1. Many fuel sources for power stations produce CO2. Which one of these does not produce CO2?
2. Which one of these answers correctly describes the stages of transfer of energy in a fossil fuel power station?
A. chemical → thermal → kinetic → electrical
B. potential → thermal → electrical
C. chemical → thermal → electrical
D. chemical → thermal → potential → electrical
3. 'Energy density' is defined as ...
A. the fraction of total energy available by combustion
B. the energy per unit volume
C. the energy per unit mass
D. the total energy available per mole
4. Which of these answers correctly describes the uses and properties of the three fossil fuels?
Most used worldwide in electricity generation
Highest efficiency in a power station
5. Fossil fuels are used more widely world wide than photovoltaic cells in electricity production. Which of the following statements does not contribute to this?
A. Photovoltaic cells are relatively expensive per kWh output
B. Photovoltaic cells have a low output per square meter
C. Photovoltaic cells do not operate 24 hrs a day
D. Photovoltaic cells do not have many suitable locations for placement
6. Which of these answers correctly describes the transportation and storage problems associated with fossil fuels?
Easiest to store on site
Easiest to transport
7. The output of a solar panel in Norway is less than that in Egypt because ...
A. There are less total daylight hours over a year in Norway.
B. The intensity of radiation is lower in Norway.
C. the solar constant is lower in Norway.
D. The albedo of the Earth is greater in Norway.
8. A hydroelectric scheme converts ...
A. gravitational to kinetic to electrical energy
B. kinetic to electrical energy
C. gravitational to mechanical energy
D. kinetic to gravitational to electrical energy
9. Which of these energy resources has the Sun as the original energy source?
10+11: These questions are about wind turbines.
10. A wind turbine generator can never be 100% efficient because ...
A. some of the air flow will retain some kinetic energy
B. the generator must be switched off in high wind speeds
C. some air will hit the generator support
D. some air will pass underneath the blades
11. A horizontal axis wind turbine of radius r is producing power with a wind speed of velocity v. In theory, if the wind speed AND radius of the turbine are both doubled, the power output will be increased by a factor of ...