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.Management Sciences
Category: Electromagnetic Induction
The self-inductance of a solenoid is increased when a soft iron core is inserted into it. This is because the soft iron core_______________?
A. Decreases the resistance of the solenoid
B. Reduces the effect of eddy current
C. Improves the flux linkage between the turns of the coil
D. Increases the mutual inductance between the solenoid and the core
Which of the following is not a unit of inductance ?
A. Henry
B. Coulomb/volt ampere
C. Volt second per ampere
D. All of the above
A dynamo converts______________?
A. mechanical energy into electrical energy
B. electrical energy into mechanical energy
C. magnetic energy into mechanical energy
D. magnetic energy into electrical energy
A.C and D.C have the same______________?
A. effect in charging a capacitor
B. effect in charging a battery
C. effect while passing through an inductance
D. heating effect through a resistance
As per Faraday’s laws of electromagnetic induction, an e.m.f. is induced in a conductor whenever 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
The only difference between construction of D.C generator and A.C generator is that of_______________?
A. carbon brushes
B. coil
C. commutator
D. magnetic field
When the motor is at its maximum speed then back emf will be______________?
A. Maximum
B. Zero
C. Intermediate values
D. No back emf
Which of the following works on torque on the current carrying conductor placed in magnetic field ?
A. galvanometer
B. ammeter
C. voltmeter
D. all of the above
cmf generated by A.C dynamo depends upon_____________?
A. number of turns in the coil
B. magnetic field strength
C. frequency of rotation
D. all of above
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