What are the importances of conversion of AC into DC?

What are the importances of conversion of AC into DC?
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Answer :

a. For traction purpose a DC series motor is most important. Examples in railways, in electrical lifts etc. b. For electrolytic and electro chemical processes such as electro plating, electrolysis, electro refining only DC is essential. c. DC is essential for battery charging, running arc lamp torch, cinema projector and for arc welding. d. It is required for operating relays, timer, telephone, circuit breakers etc.
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