Q.1
A conductor carries 125 amperes of current under 60° to a magnetic field of 1.1 tesla. The force on the conductor will be nearly
Q.2
A crack in the magnetic path of an inductor will result in
Q.3
A laminated iron core has reduced eddy-current losses because
Q.4
In case of an inductance, current is proportional to
Q.5
Lenz's law is a consequence of the law of conservation of
Q.6
The inductance of a coil will increase under all the following conditions except
Q.7
The self-inductance of the coil may be defined as equal to the e.m.f. induced in volts when the current in the circuit changes at the rate of unit Weber turns.
Q.8
An average voltage of 10 V is induced in a 250 turns solenoid as a result of a change in flux which occurs in 0.5 second. The total flux change is
Q.9
The law that the induced e.m.f. and current always oppose the cause producing them is due to
Q.10
Current changing from 8 A to 12 A in one second induced 20 volts in a coil. The value of inductance is
Q.11
Which of the following inductor will have the least eddy current losses?
Q.12
If current in a conductor increases then according to Lenz's law self-induced voltage will
Q.13
Two coils have inductances of 8 mH and 18 mH and a coefficient of coupling of 0.5. If the two coils are connected in series aiding, the total inductance will be
Q.14
As per Faraday's laws of electromagnetic induction, an e.m.f. is induced in a conductor whenever it
Q.15
The coefficient of coupling between two air core coils depends on
Q.16
Air-core coils are practically free from
Q.17
The magnitude of the induced e.m.f. in a conductor depends on the
Q.18
A coil induces 350 mV when the current changes at the rate of 1 A/s. The value of inductance is
Q.19
The direction of induced e.m.f. can be found by
Q.20
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
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