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Thursday 24 November 2011

Type of Renewable and Non-renewable Energy


1. In the 1830s, a British astronomer John Herschel used a solar collector box to cook food during an expedition to Africa. Now, people are trying to  use the sun’s energy for many other purposes. Besides its continuous supply and advantages, the  use of solar energy is increasing. Solar energy is also becoming more and more important because energy from petrol will disappear soon.

2.  Biomass energy or bioenergy  (energy from organic matter) has been used for thousands of years, ever since people started burning wood  to cook or to keep warm .And today, wood is still our largest biomass energy resource.However, many other sources of  biomass can now be used, including plants,residues from agriculture or forestry and the organic component of municipal and industrial wastes. Even the fumes of landfills can be used as a biomass energy source.The use of biomass can also help increase profits for the agricultural industry.  

 3. Hydroelectric  power is the biggest source of renewable energy,providing 14% of the world's electricity.Fast flowing water released from dams in mountainous area can turn water turbines to produce electricity.In most cases, water is stored behind a dam in a reservoir.Water pressure forces the water onto the blades of a turbine.Rotation of the generator  represents the kinetic energy which is finally transformed into electric energy  will be supplied for public usage. Ocean or tidal waves can also be used to generate electricity.

 4. Coal  is a fossil fuel formed over millions of years from plants.It is a hard,black coloured rock-like substance made of carbon, hydrogen, oxygen, nitrogen and sulphur. Coal is mainly burned in power stations to produces electricity.When  coal is burned,it produces a large amount of carbon dioxide, one of the gases responsible for the greenhouse effect.

 5. Petroleum is an oily, flammable, liquid solution of yellowish green or black colour, which occurs naturally in earth.It is formed from decomposed plants and animals a long time ago. When distilled, gasoline, kerosene, paraffin, fuel oil, benzene, bitumen and  others.These products are used in houses for heating and cooking and in factories as a source of heat energy.They are also  used to provide fuel for transport and in power stations. However, their uses,especially petrol and diesel,produce a large amount carbon dioxide.They also produce other poisonous gases that may harm the environment and people's health.

 6. Natural gas is formed from the remaining plants,animals and microorganisms that lived millions of year ago.Natural gas  a colourless and odourless in its pure form. When  burned,it  given off a great deal of energy.Unlike other fossil fuels,natural gas emits lower levels of harmful by-products into the air.Natural gas has many applications,commercially,in your home,in industry and even in the transportation sector.
 
          Type of Renewable and Non-renewable Energy

Wednesday 23 November 2011

Renewable or Non-renewable Energy Resources


What are Renewable or Non-renewable Energy Resources?

1.Energy resources are divided into  two groups:
·        Renewable energy
·        Non-renewable energy

2.Renewable energy can be replenished when
   used up.

3. Non-renewable energy  cannot be replenished
    when used up.

4. Renewable energy resources include solar 
    energy, wind energy, geothermal energy from
    inside the Earth, biomass from plants and   
    hydropower from water stores in reservoirs
    and oceans in the form of wave.
5. We get most of our energy from 
    non-renewable energy resources, which 
    include crude oil, natural gas and coal.
    They are called fossil fuels because
    they are formed over millions of years
    from the remains of dead plants and animals
    by the action of heat from the Earth’s core 
    and pressure from the rock and soil. Fossil 
    fuels are continually produced by decaying
    plant and animal matter, but the rate of
    their production is extremely slow, very 
    much slower than the rate at which we 
    use them.





Renewable Energy


Non-renewable Energy






Tuesday 22 November 2011

Kinetic Energy and Potential Energy

 

Kinetic Energy

Kinetic energy is related to motion of waves, electrons, atoms, molecules , substances and objects.

Potential Energy

Potential  energy is the energy that is stored and related to the position of something.

Let sing together


Answer ( Check Your Understanding)-Transformation Of Energy

A Burning Candle
chemical  energy   →  

light  energy  + heat  energy
lamp

electrical energy    →    

light energy + heat energy
rice cooker


 electrical energyheat energy
Computer

electrical energy

light energy + sound energy
Hair  dryer

electrical energy→  

heat energy + sound energy
Calculator

 solar  energy →  

electrical energy → 

light energy


Solar powered signal light

 solar energy

electrical energy → 

light energy