CBSE Class 10th Physics Notes for Chapter 5 -Sources of Energy

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GOOD SOURCE OF ENERGY
A good source of energy is the one that:

• does a large amount of work per unit volume
• is easily accessible
• is easy to store and transport
• is economical

 
CONVENTIONAL SOURCES OF ENERGY

1. Fossil fuels: These are the fuels that took millions of years to form. Fossil fuels are non-renewable and therefore should be conserved. Burning fossil fuels has adverse effect on the environment.
2. Thermal Power Plant: Fossil fuels are burnt every day in power stations to heat up water to produce steam which further runs the turbine to generate electricity. The term thermal power plant is used since fuel is burnt to produce heat energy which is converted into electrical energy.
3. Hydro Power Plants: These power plants convert the potential energy of falling water into electricity.

 
IMPROVEMENTS IN THE TECHNOLOGY FOR USING CONVENTIONAL SOURCES OF ENERGY

1. Bio-mass: It contains up to 75% methane. It burns without smoke and leaves no residue.
2. Wind energy: To generate electricity, the rotary motion of the windmill driven by the wind is used to turn the turbine of the electric generator.

 
ALTERNATIVE OR NON-CONVENTIONAL SOURCES OF ENERGY

1. Solar Energy: The energy of the sun is harnessed to produce electrical energy with the help of solar panels.
2. Tidal Energy: The difference in sea levels during the high tide and the low tide can be harnessed by constructing a dam across a narrow opening to the sea. The energy thus obtained is called tidal energy.
3. Ocean Thermal Energy: The difference in temperature is exploited to obtain energy in ocean thermal energy conversion plants.
4. Geothermal Energy: The steam generated at hot springs is harnessed to produce geothermal energy.
5. Nuclear Energy: Nuclear fission is used to generate heat which is used to produce steam to drive turbines and produce energy.