162. In each of the three coils of a three phase generator, an alternating voltage having an r.m.s. value of 220 V is induced. Which of the following values is indicated by the voltmeters?
A. 220 V
B. 220 j V
C. 220Z V
D. none of the above
163. Which of the following equations is valid for a balanced load on a starts circuit with a neutral conductor in a four wire star circuit?
A. IN = IR Iy + IB =
B. IN = IR ? Iy + IB
C. IN = IR + ly ?IB
D. IN = (VR + Vy + VB)/R
164. The true power drawn by a balanced three-phase consumer for line voltage V and line current I is given by
A. V I cos 4)
B.v I cos 4)
C. 3 V I cos
165. . An electric iron designed for 110 V A.C. supply was rated at 500 W. It was put across a 220 V supply. Assuming that at 110 V it supplied 500 W output, (i.e., no losses) at the new voltage it will supply
B. 2000 W
C. 500 W
D. 250 W
166. From the Fig. 5.16 it can be concluded that
A. v leads i by n/2
B. v lags i by it/2
C. v leads i by n
D. v lags i by n
167. A coil is connected across a 200 V, 50 Hz supply and takes a current of 10 A. The loss in the coil is 1000 W. The impedance and resistance of the coil are
A. 10 L-1, 8 S-2
B. 15 0, 8 L2
C. 20 12, 10
168. In an A.C. circuit (sine wave) with R and L in series
A. voltage across and L are 180? out of phase
B. the voltage across R lags the voltage across L by 90?
C. the voltage across R leads the voltage across L by 90?
D. voltage across R and L are in phase
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