QUESTIONS: 1. What are fossil fuels important? 2. Distinguish between reserves and resources. 3. What are the advantages of surface mining of coal compared to underground mining? What are the disadvantages of surface mining? 4. Compared the enviromental impacts of the use of coal and the use of oil. 5. What are some limiting factors in the development of new hydroelectric generating sites? 6. What factors limit the development of tidal power as a source of electricity? 7. In what parts of the world is geotermal energy available? What creats it? 8. Why can wind be considerd a form of solar energy? 9. Compared a passive sola-heating system with an active sola heating system. 10. What problems are associated with the use of solid waste as a source of energy? 11. List three energy conservation techniques.

1. Group 12:
1. PHAI MINEA [Leader: 0966153104] (ID: 2119055)
2. LAO SOKKEANG [0966973633] (ID: 2119639)
3. OL KIMMEY [098661176] (ID: 2120522)
4. RITH CHHAINGIM [0969071860] (ID: 2121245)

2. REVIEW QEUSTIONS
QUESTIONS:
1. What are fossil fuels important?
2. Distinguish between reserves and resources.
3. What are the advantages of surface mining of coal compared to underground mining?
What are the disadvantages of surface mining?
4. Compared the enviromental impacts of the use of coal and the use of oil.
5. What are some limiting factors in the development of new hydroelectric generating
sites?
6. What factors limit the development of tidal power as a source of electricity?
7. In what parts of the world is geotermal energy available? What creats it?
8. Why can wind be considerd a form of solar energy?
9. Compared a passive sola-heating system with an active sola heating system.
10. What problems are associated with the use of solid waste as a source of energy?
11. List three energy conservation techniques.

3. ANSWER
1. What are fossil fuels important?
Answer 1:
The United States gets 81% of its total energy from oil, coal, and natural gas, all
of which are fossil fuels. We depend on those fuels to heat our homes, run our
vehicles, power industry and manufacturing, and provide us with electricity.
2. Distinguish between reserves and resources.
Answer 2:
Resources" means using your money; "reserves" means using my money.
Differences can be enormous. Government agencies and academic scientists tend to
estimate resources, whereas industrial/oil companies appraise only reserves.
3. What are the advantages of surface mining of coal compared to underground mining?
What are the disadvantages of surface mining?
Answer 3:
Surface mines offer advantages and disadvantages when compared to
underground mining. Amongst the advantages are that it is cheaper, can recover more
of the resource (usually up to 100% within the mining excavation), is safer and can use
larger-scale mining equipment offering higher production rates.
4. Compared the enviromental impacts of the use of coal and the use of oil.
Answer 4:
 Environmental impact of Coal
 Several principal emissions result from coal combustion: Sulfur dioxide
(SO2), which contributes to acid rain and respiratory illnesses. Nitrogen
oxides (NOx), which contribute to smog and respiratory illnesses.
Particulates, which contribute to smog, haze, and respiratory illnesses
and lung disease.
 Environmental impact of oil
 Oil pollution can have a devastating effect on the water environment, it
spreads over the surface in a thin layer that stops oxygen getting to the
plants and animals that live in the water. Oil pollution: harms animals
and insects. prevents photosynthesis in plants.

4. 5. What are some limiting factors in the development of new hydroelectric generating
sites?
Answer 5:
Among physical factors two prime factors are quantity of water and degree of
slope. The greater the quantity of water available, and steeper or longer the slope, the
greater is the energy generated.
6. What factors limit the development of tidal power as a source of electricity?
Answer 6:
Tides are more predictable than the wind and the sun. Among sources of
renewable energy, tidal energy has traditionally suffered from relatively high cost and
limited availability of sites with sufficiently high tidal ranges or flow velocities, thus
constricting its total availability.
7. In what parts of the world is geotermal energy available? What creats it?
Answer 7:
 U.S. geothermal power plants are located in the West
 Most of the geothermal power plants in the United States are in western
states and Hawaii, where geothermal energy resources are close to the
earth's surface. California generates the most electricity from
geothermal energy.
8. Why can wind be considerd a form of solar energy?
Answer 8:
Wind energy is actually an indirect form of solar energy: wind blows because the
sun unevenly heats different areas of our atmosphere due to the earth's rotation and
differences in surface areas.
9. Compared a passive sola-heating system with an active sola heating system.
Answer 9:
While passive solar heating only absorbs solar energy it does nothing more to
enhance the energy absorbed. Whereas, active solar energy heating takes the help of
mechanical equipment that in turn enhances the conversion rate of solar energy to heat.
10. What problems are associated with the use of solid waste as a source of energy?
Answer 10:

5. However, this technology also has several disadvantages such as landfills
requiring a large surface area and pollution problems, including ground water
pollution, air pollution, and soil contamination.
11.List three energy conservation techniques.
Answer 11:
• Turn your refrigerator down. ...
• Use energy-efficient light bulbs. ...
• Clean or replace air filters as recommended. ...
• Do full loads. ...
• Use smart power strips. ...
• Air-dry dishes and clothes. ...
• Bake with glass or ceramic pans. ...
• Cook using the right-sized burner.