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In This Video :
Fuel is one of the most important resources of energy that humans depend on to get energy.

Fuel: It is any substance that produces thermal energy when it is burned.
The main source of thermal energy that is produced by fuel, is the Sun.
Different forms of fuels:
• Oil - natural gas - coal - wood.
• Uses of some different forms of fuels:
1. Cooking food, where coal, natural gas or wood may be used.
2. Generating electricity, where oil, natural gas or coal may be used.
3. Warming, where coal or wood may be used.
4. Operating all means of transportation, where gasoline (oil) or natural gas may be used.

Energy resources
1. Renewable energy resources :
• They are natural resources that can be replaced after a short period of time of
use, such as water, solar energy and wind energy.

2. Non-renewable energy resources :
• They are natural resources that are used at a rate faster than they can be
replaced, such as coal, natural gas and oil.


Types of fuels
1. Biofuel : It is a fuel that is produced from living organisms that can be planted.
• Its primary source : The Sun.
• Biofuel is a renewable energy resource.

Examples:
• Wood
• Charcoal
• Some types of plants such as grass, corn and wood chips can be used to make a liquid fuel.

2. Fossil fuel : It is a fuel that is produced from old living organisms (plants or
animals) that were buried and decomposed over a long period of time.
• Its primary source : The Sun.
• Fossil fuel is a non-renewable energy resource.

Examples:
• Oil and natural gas are formed when the remains of marine organisms were
decomposed.
• Coal is formed when the remains of plants were decomposed.

Conservation of oil
• Reducing the use of private vehicles.
• Using of public means of transportation .
Conservation of water
•Avoid wasting or polluting water.
• Growing plants that don't need large amounts of water for irrigation.
Conservation of electricity
•Turning off lights when they are not needed.
• Unplugging electrical appliances when not in use.
• Burning of coal and oil produces carbon dioxide gas which causes :
-Acid rains. - Global warming.
• Acid rains cause :
- Death of trees.
- Decomposition and dissolving of some rocks.
- Chemical changes in the structure of lakes causing the death of fish.
- Chemical changes in the structure of soil.
• Global warming :
- Increasing the amount of carbon dioxide gas in the air causing increasing the
temperature of the Earth's surface.

Conservation of fossil fuels
•Turning off lights when you are not in the room.
•Walking or using bicycles instead of driving a car.
• Replacing fossil fuels with renewable energy resources such as solar energy,
hydroelectric energy and wind energy.

بالتوفيق
مستر احمد الباشا