A single-phase ac voltage regulator has a resistive load of R= 10 ohms, and the input voltage is Vs = 240 V, 50 Hz. The delay angle of each of the Thyristors is alpha = pi/2. Determine:

(a) The rms value of the output voltage.

(b) The Fourier coefficients of the fundamental, 11th and 13th current harmonics.