previous questions
1. Which three-phase connection can be used in a transformer to introduce a phase difference of 30° between its output and corresponding input line voltages:
(a) Star - Star
(b) Star - Delta
(c) Delta - Delta
(d) Delta - Zigzag
2. The conduction loss versus device current characteristic of a power MOSFET is best approximated by
(a) a parabola
(b) a straight line
(c) a rectangular hyperbola
(d) an exponentially decaying function
3. Under no load condition, if the applied voltage to an induction motor is reduced from the rated voltage to half the rated value:
(a) the speed decreases and the stator current increases
(b) both the speed and the stator current decrease
(c) the speed and the stator current remain practically constant
(d) there is negligible change in the speed but the stator current decreases
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