When both the inductance and resistance of a coil are doubled the value of Time constant is halved Time constant remains unchanged Final steady current is doubled Initial rate of rise of current is doubled TRUE ANSWER : ? YOUR ANSWER : ?
While comparing magnetic and electric circuits, the flux of magnetic circuit is compared with which parameter of electrical circuit? Current Conductivity Current density E.M.F TRUE ANSWER : ? YOUR ANSWER : ?
The unit of magnetic flux is Ampere/metre Henry Weber Ampere-turn/weber TRUE ANSWER : ? YOUR ANSWER : ?
Hard steel is suitable for making permanent magnets because It has good residual magnetism Its hysteresis loop has large area Its mechanical strength is low Its mechanical strength is high TRUE ANSWER : ? YOUR ANSWER : ?
In a magnetic material hysteresis loss takes place primarily due to Molecular friction Flux density lagging behind magnetizing force Rapid reversals of its magnetization It high retentivity TRUE ANSWER : ? YOUR ANSWER : ?
A material for good magnetic memory should have Low hysteresis loss High permeability High retentivity Low retentivity TRUE ANSWER : ? YOUR ANSWER : ?
The initial rate of rise of current through a coil of inductance 10 H when suddenly connected to a D.C. supply of 200 V is ___________Vs 70 20 500 50 TRUE ANSWER : ? YOUR ANSWER : ?
Permeability in a magnetic circuit corresponds to_________ in an electric circuit. Resistivity Conductivity Resistance Conductance TRUE ANSWER : ? YOUR ANSWER : ?
The relative permeability of a ferromagnetic material is More than 10 More than 100 Ωr 1000 More than one Less than one TRUE ANSWER : ? YOUR ANSWER : ?
If the area of hysteresis loop of a material is large, the hysteresis loss in this material will be Small Zero None of the listed here Large TRUE ANSWER : ? YOUR ANSWER : ?