Objective Questions Short notes Objective questions (Answers are given below) Which of the following connections is best suitedfor 3-phase, 4-wire service ?(a) Δ − Δ (b) Y − Y(c) Δ − Y (d) Y − Δ In a three-phase Y-Y transformer connection,neutral is fundamental to the(a) suppression of harmonics(b) passage of unbalanced currents due tounbalanced … Read more
Objective Questions Short notes Objective questions (Answers are given below) A transformer transforms(a) frequency(b) voltage(c) current(d) voltage and current. Which of the following is not a basic element ofa transformer ?(a) core(b) primary winding(c) secondary winding(d) mutual flux. In an ideal transformer,(a) windings have no resistance(b) core has no losses(c) core has infinite permeability(d) all … Read more
Objective Questions Short notes Objective questions (Answers are given below) One of the main advantages of Swinburne’s testis that it(a) is applicable both to shunt and compoundmotors(b) needs one running test(c) is very economical and convenient(d) ignores any charge in iron loss The main disadvantage of Hopkinson’s test forfinding efficiency of shunt d.c. motors is … Read more
Objective Questions Short notes Objective questions (Answers are given below) The speed of a d.c. motor can be controlled byvarying(a) its flux per pole(b) resistance of armature circuit(c) applied voltage(d) all of the above The most efficient method of increasing thespeed of a 3.75 kW d.c. shunt motor would bethe ………..method.(a) armature control(b) flux control(c) … Read more