Top 50+ Solved Electromagnetic Induction MCQ Questions Answer
Q. The property of coil by which a counter e.m.f. is induced in it when the current throughthe coil changes is known as
a. self-inductance
b. mutual inductance
c. series aiding inductance
d. capacitance
Q. As per Faraday's laws of electromagnetic induction, an e.m.f. is induced in a conductorwhenever it
a. lies perpendicular to the magnetic flux
b. lies in a magnetic field
c. cuts magnetic flux
d. moves parallel to the direction of the magnetic field
Q. Which of the following circuit element stores energy in the electromagnetic field ?
a. Inductance
b. Condenser
c. Variable resistor
d. Resistance
Q. The inductance of a coil will increase under all the following conditions except
a. when more length for the same number of turns is provided
b. when the number of turns of the coil increase
c. when more area for each turn is provided
d. when permeability of the core increases
Q. Higher the self-inductance of a coil,
a. lesser its weber-turns
b. lower the e.m.f. induced
c. greater the flux produced by it
d. longer the delay in establishing steady current through it
Q. In an iron cored coil the iron core is removed so that the coil becomes an air cored coil.The inductance of the coil will
a. increase
b. decrease
c. remain the same
d. initially increase and then decrease
Q. An open coil has
a. zero resistance and inductance
b. infinite resistance and zero inductance
c. infinite resistance and normal inductance
d. zero resistance and high inductance
Q. Both the number of turns and the core length of an inductive coil are doubled.Its self-inductance will be
a. unaffected
b. doubled
c. halved
d. quadrupled
Q. If current in a conductor increases then according to Lenz's law self-induced voltage will
a. aid the increasing current
b. tend to decrease the amount of cur-rent
c. produce current opposite to the in-creasing current
d. aid the applied voltage
Q. The direction of incViced e.m.f. can be found by
a. Laplace's law
b. Lenz's law
c. Fleming's right hand rule
d. Kirchhoff s voltage law
Q. Air-core coils are practically free from
a. hysteresis losses
b. eddy current losses
c. both (a) and (b)
d. none of the above
Q. The magnitude of the induced e.m.f. in a conductor depends on the
a. flux density of the magnetic field
b. amount of flux cut
c. amount of flux linkages
d. rate of change of flux-linkages
Q. Mutually inductance between two magnetically-coupled coils depends on
a. permeability of the core
b. the number of their turns
c. cross-sectional area of their com-mon core
d. all of the above
Q. A laminated iron core has reduced eddy-current losses because
a. more wire can be used with less D.C. resistance in coil
b. the laminations are insulated from each other
c. the magnetic flux is concentrated in the air gap of the core
d. the laminations are stacked vertf-cally
Q. The law that the induced e.m.f. and current always oppose the cause producing them isdue to
a. Faraday
b. Lenz
c. Newton
d. Coulomb