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

MAGNETIC HYSTERESIS

Objective Questions Short notes Objective questions (Answers are given below) Permanent magnets are normally made of(a) aluminium (b) wrought iron(c) cast iron (d) alnico alloys A coil of 1000 turns is wound on a core.A current of 1 A flowing through the coilcreates a core flux of 1 mWb. The energystored in the magnetic field … Read more

ELECTROMAGNETIC INDUCTION

Objective Questions Short notes Objective questions (Answers are given below) According to Faraday’s Laws of Electromagnetic Induction, an e.m.f. is induced in a conductor whenever it (a) lies in a magnetic field(b) cuts magnetic flux(c) moves parallel to the direction of themagnetic field(d) lies perpendicular to the magnetic flux. A pole of driving point admittance … Read more

CAPACITANCE

Objective Questions Short notes Objective questions (Answers are given below) A capacitor consists of two(a) insulation separated by a dielectric(b) conductors separated by an insulator(c) ceramic plates and one mica disc(d) silver-coated insulators The capacitance of a capacitor is NOTinfluenced by(a) plate thickness(b) plate area(c) plate separation(d) nature of the dielectric A capacitor that stores … Read more

ELECTROSTATICS

Objective Questions Short notes Objective questions (Answers are given below) The unit of absolute permittivity of a medium is(a) joule/coulomb(b) newton-metre(c) farad/metere(d) farad/coulomb If relative permittivity of mica is 5, its absolute permittivity is(a) 5 ε0 (b) 5/ε0(b) 5/ε0 (c) ε0/5 (d) 8.854 × 10−12 Two similar electric charges of 1 C each are placed … Read more