Question
(a) What do you understand by the term hydroelectric power?
(b) Explain the energy changes taking place in a hydroelectric dam?
(b) Explain the energy changes taking place in a hydroelectric dam?
✓
Answer
(a) Hydroelectric power: Hydroelectric power is the power derived from energy of
falling water or fast running water. A hydroelectric power plant is an arrangement in which the kinetic energy of flowing water is transformed into electric energy and the electric energy so generated is called hydroelectric energy.
(b) Energy changes taking place in a hydroelectric dam:
1. As the water flows into reservoir from the catchment area, the kinetic energy of flowing water changes to potential energy.
2. As the water is released through control valve, the potential energy of water changes to kinetic energy.
3. As the water flowing at a high speed strikes the blades of the turbine, its kinetic energy changes to rotational kinetic energy of the turbine.
4. As the turbine is coupled to the shaft of generator, the rotational kinetic energy of turbine changes to the rotational kinetic energy of armature.
5. As the coils of armature rotate in magnetic field, the rotational kinetic energy of armature changes to the electric energy in its coils.
falling water or fast running water. A hydroelectric power plant is an arrangement in which the kinetic energy of flowing water is transformed into electric energy and the electric energy so generated is called hydroelectric energy.
(b) Energy changes taking place in a hydroelectric dam:
1. As the water flows into reservoir from the catchment area, the kinetic energy of flowing water changes to potential energy.
2. As the water is released through control valve, the potential energy of water changes to kinetic energy.
3. As the water flowing at a high speed strikes the blades of the turbine, its kinetic energy changes to rotational kinetic energy of the turbine.
4. As the turbine is coupled to the shaft of generator, the rotational kinetic energy of turbine changes to the rotational kinetic energy of armature.
5. As the coils of armature rotate in magnetic field, the rotational kinetic energy of armature changes to the electric energy in its coils.
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