Answer to Question #117359 in Electrical Engineering for fadhli

Question

(a) An alternating voltage has the equation v(t) = 222 sin (314t + 70°). What are the values of r.m.s. voltage, average voltage, frequency and the instantaneous voltage when t = 5 ms.

Answer 1

Given;

Equation v (t) = 222 sin (314t + 70⁰) and t = 5 ms

a) R.m.s voltage

    =(222/ square root of 2)

        = 156.98v

b) Average voltage

 Vavg = 0 [Over a time period both positive and negative areas are equal or for full cycle]

c) Frequency

f =  (314/2*3.14)

  = 50 Hz

c) Instantaneous voltage

at t = 5 ms

            V(t)=222sin {(314*5)/1000 +70 degrees)

              = 222 sin ( 1.57 + 1.22 rad)

             = 222 sin (2.792 rad)

             = 76.246v

Therefore; V (t) = 76.246v