Question

R.M.S value of the sinusoidal waveform V=48sin(6.5πt+89π÷46.8).

(a) 33.94 V

(b) 33.56 V

(c) 33.12 V

(d) 33.78 V

The question was asked by my school principal while I was bunking the class.

Enquiry is from Speed Control of Shunt or Separately Excited Motors topic in portion Speed Control of Direct Current Motors & Induction Motors of Electric Drives

Answer 1

The correct choice is (a) 33.94 V

For explanation I would say: R.M.S value of the sinusoidal waveform is Vm÷2^½ = 48÷2^½ = 33.94 V and r.m.s value of the trapezoidal waveform is Vm÷3^½. The peak value of the sinusoidal waveform is Vm.