Answer / dinesh lokhande

Basically frequeny of supply depends upon generated voltage
frequency which is guided by universal formula

N=(120*F)/P

Where;
N = Synchronous speed of Generator
F = Frequency
P = No of poles of generator

Frequeny in North America is 60 hz because designed
generators are for 60 hz as per above formula and vice
versa for Europe.

Hope this is clear.

Answer / shaikk

George Westinghouse did his original engineering using 133
1/3 Hz. Westinghouse had an steam engine driven alternator
set running at 2000 rpm (By 1886 mechanical engineers liked
to have steam engines in integral numbers of rpm) and with 8
poles the set produced 8000 cycles per minute or 133 1/3 Hz.
This was good for lighting as there was no flicker but it
turned out it was too high for motors later developed.

In the early years of ac there were many frequencies:
each engineering team seemed to pick their own. Early
frequencies in the US were 133 1/3, 125, 83 1/3, 66 2/3, 60,
50, 40, 30, 25 Hz. When Tesla joined Westinghouse, it was
using 133 1/3 Hz. Tesla insisted upon 60 Hz because his ac
induction motor was designed for 60 Hz and apparently
wouldn't work at 133 1/3 Hz.

Answer / ritika

it is just a convention and nothing else.the machinery in n
America is being designed using 60 hz.

Answer / shyam

in north america there ideal operation(with out losses in
transmission lines) is possible at 60hz bcoz they are
available to maintain generator at 60hz freaq due to
efficient use of the available resouces

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