Related InterviewSolutions

• In a 3-phase system, ___th harmonic has negative phase sequence of RBY.(a) 9 (b) 13 (c) 5 (d) 15
• The r.m.s. value of the complex voltage given by v = + 16√2sinωt + 12√2 sin3ωt   is(a) 20√2 (b) 20 (c) 28√2 (d) 192
• When a pure inductive coil is fed by a complex voltage wave, its current wave (a) has larger harmonic content (b) is more distorted(c) is identical with voltage wave (d) shows less distortion.
• Non-sinusoidal wave forms are made up of (a) different sinusoidal wave forms (b) fundamental and even harmonics (c) fundamental and odd harmonics (d) even and odd harmonics only
• The positive and negative halves of a complex wave are symmetrical when (a) it contains even harmonics(b) phase difference between even harmonics and fundamental is 0 or π (c) it contains odd harmonics (d) phase difference between even harmonics and fundamental is either π/2 or  3π/2. 
• A complex current wave is given by the equation i = 14sinωt  + 2sinωt. The r.m.s. value of the current is ___ ampere. (a) 16 (b) 12 (c) 10 (d) 8
• Which of the following harmonic voltage components in a 3-phase system would be in phase with each other? (a) 3rd, 9th, 15th etc. (b) 7th, 13th, 19th etc. (c) 5th, 11th, 17th etc. (d) 2nd, 4th, 6th etc
• A complex voltage wave is applied across a pure capacitor. As compared to the fundamental voltage, the reactance offered by the capacitor to the third harmonic voltage would be (a) nine time (b) three times (b) one-third (d) one-ninth
• Determine whether the following two waves are of the same shape e = 10sin ( ωt + 30º) – 50 sin(3ωt – 60º) + 25 sin (5ωt + 40º) i = 1.0 sin (ωt – 60º) + 5 sin (3ω t – 150º) + 2.5cos (5ω t – 140º)