SERIES A.C. CIRCUITS

Objective Questions Short notes Objective questions (Answers are given below) In a series R-L circuit, VL—VR by—degrees.(a) lags, 45 (b) lags, 90(c) leads, 90 (d) leads, 45 The voltage applied across an R-L circuit isequal to—of VR and VL.(a) arithmetic sum (b) algebraic sum(c) phasor sum (d) sum of the squares. The power in an … Read more

COMPLEX NUMBERS

Objective Questions Short notes Objective questions (Answers are given below) The symbol j represents counterclockwiserotation of a vector through—degrees.(a) 180 (b) 90(c) 360 (d) 270 The operator j has a value of(a) + 1 (b) − 1(c) − 1 (d) + 1 The vector j5 E is the same as vector(a) jE (b) j2 E(c) … Read more

A.C. FUNDAMENTALS

Objective Questions Short notes Objective questions (Answers are given below) An a.c. current given by i = 14.14 sin (ωt +π/6) has an r.m.s value of — amperes.(a) 10(b) 14.14(c) 1.96(d) 7.07and a phase of — degrees.(e) 180(f) 30(g) − 30(h) 210 If e1 = A sin ωt and e2 = B sin (ωt − … Read more

ELECTRICAL INSTRUMENTS AND MEASUREMENTS

Objective Questions Short notes Objective questions (Answers are given below) The kWh meter can be classified as a/aninstrument:(a) deflecting (b) digital(c) recording (d) indicating The moving system of an indicating type ofelectrical instrument is subjected to :(a) a deflecting torque(b) a controlling torque(c) a damping torque(d) all of the above The damping force acts on … Read more

ELECTROCHEMICAL POWER SOURCES

Objective Questions Short notes Objective questions (Answers are given below) Active materials of a lead-acid cell are :(a) lead peroxide (b) sponge lead(c) dilute sulphuric acid (d) all the above During the charging of a lead-acid cell :(a) its cathode becomes dark chocolate brownin colour(b) its voltage increases(c) it gives out energy(d) specific gravity of … Read more