a) 7.4 millivolts b) 4.4 millivolts c) 5 millivolts d) 1 millivolts Ans: (b)
a) Alternating current and voltage waveforms do not in general, contain even harmonics b) Alternating current and voltage waveforms in general do not contain odd harmonics c) Alternating current and voltage waveforms in general contain even harmonics d) Alternating current and voltage waveforms contain even and odd harmonics in general Ans: (a)
a) True b) False Ans: (a)
a) Reduces the amplitude of harmonics in current wave b) Enlarges the amplitude of harmonics in current wave c) Does not effect the wave shape at all d) Reduces the amplitude of the harmonics in the current wave and causes the latter to approach more nearly to the sinusoidal wave shape than e.m.f. wave Ans: (a)
a) True b) False Ans: (b)
a) True b) False Ans: (a)
a) It is the cosine of the angle of phase difference between the voltage and current waves b) It is the cosine of the angle of phase difference between the two complex wave c) It is the cosine of the angle of phase difference between two “equivalent sine waves” having respectively r.m.s. values equal to those of the voltage and current in the circuit d) It is the sine of the angle of phase difference between the two complex waves Ans: (c)
a) Electrostatic field only b) Electromagnetic field only c) (a) or (d) d) None of the above Ans: (c)
a) Zero b) 25° C c) -40° C d) 32° C Ans: (c)
a) Chromium b) Magnesium c) Nickel d) Molybdenum Ans: (c)