A generator
is a device that converts mechanical energy in to electrical
energy (electricity).
A coil of
wire generates electricity when a permanent magnet is
rotated to produce electricity.
Dry cell is the chemical
method to produce electricity.
A battery
is a chemical source for generatingelectrical energy.
The electricity
generated by conversion of kinetic energy of water
is called hydroelectric power.
The use of wind
energy as a source for generating electrical energy is
called wind power.
The electrical
device that converts AC to DC is called a rectifier.
Nuclear power is generated
by breaking nuclei of some heavy elements like uranium, plutonium
etc.
Generating
electricity by means of heat produced by burning of fuels like coal,
gas or oil in thermal power station is called thermal power.
Alternating
current changes its direction every moment.
When there is a
relative motion between a magnet and a coil and a coil of wire, electric
current starts flowing in the coil. This phenomenon is called electromagnetic
induction.
The energy
stored in a small amount of nuclear fuel is enormous. For example, 1 kg of
nuclear fuel contains nearly three million times
the energy that is obtained from 1kg of coal.
A resistor
is a component that resists the flow of currant.
Unit of
resistance is ohms and denoted by Ω.
A device that
cans store temporarily an electric charge is called capacitors.
Capacitance of
a capacitor is measured in farad and denoted by “F”.
Diode is a device
that lets current flow in only one direction.
A diode has two
terminals called the anode and the cathode.
Transistor is a three
terminal device. These are used as switches and amplifiers in an
electronic system.
The current
which flow only in one direction is called direct
current.
The current
which changes its direction is called alternating current.
In hydro power………is used to run
turbines.
a) Moving water
b) Electrical energy
c) Wind energy
d) Heat energy
