Answer / r k sinha

there r mainly two reason for using sine wave in ac supply:
(i)it is easy to produce by rotating coil under magnetic feild..and
(ii)all the function exist in world can be break down under the summation of many sine function by a method called fourier transformation..so it is easy for us to derive all result for sine wave...

Answer / a.n.v.kartik

In Maths differentiation of sin is cos and for cos in minus
sin.double differentiative of sin is minus sin.so from this
we can infer that the same function is repeating after two
differentiation.so when one asks about AC supply v ll draw
sinusoidal waveform...if v use sin function the calculations
will be easy...this is the reason....

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