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3 disadvantages :
The shock of the ac is attractive but the shock of dc is repulsive.
At high voltages, it is more dangerous to work with ac than dc.
In the processes like electrorefining, electroplating etc. , one can not use the ac.
In these processes, only dc is used.
Galvanometer
A galvanometer is an instrument that can detect the presence of a current in a circuit.
The pointer remains at zero (the centre of the scale) for zero current flowing through it.
It can deflect either to the left or to the right of the zero mark depending on the direction
of current.
Power generation
Electricity generation is the process of generating electric power from sources
of primary energy. For electric utilities, it is the first process in the delivery of electricity
to consumers. Electricity is most often generated at a power
station by electromechanical generators, primarily driven by heat engines fuelled
by combustion or nuclear fission but also by other means such as the kinetic energy of
flowing water and the wind.
Transmission of power from the generating station:
At the generating station, the electric power is generated at 11,000 volts or 11 kV
