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In electromagnetic induction, the induce...

In electromagnetic induction, the induced charge in a coil is independent of

A

change in the flux

B

time

C

resistance in the circuite

D

none of the above

Text Solution

Verified by Experts

The correct Answer is:
B
We know that `e=(dvarphi)/(dt)`
but e=iR and `i=(dq)/(dt)implies(dq)/(dt) R=dq=(dvarphi)/(R )`
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Explore conceptually related problems

Answer question numbers (a)-(d) on the basis of your understanding of the following paragraph and the related studied concepts : The phenomenon of electromagnetic induction is the production of induced current in a coil placed in a region where the magnetic field changes with time. The magnetic field may change due to a relative motion between the coil and a magnet placed near to the coil. If the coil is placed near to a current carrying conductor, the magnetic field may change either due to a change in the current through the conductor or due to the relative motion between the coil and conductor. The direction of the induced current is given by the Fleming's right-hand rule. What is the cause of current induced in a coil in electromagnetic induction phenomenon ?

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Knowledge Check

  • Self inductance of a coil is independent of

    A
    current flowings in the coil
    B
    emf induced in the coil
    C
    rate of change of current in the coil
    D
    All of these

  • In electromagnetic induction, the induced emf is independent of

    A
    change of flux
    B
    time
    C
    number of turns in the coil
    D
    resistance of the coil

  • Assertion (A) : The phenomenon of electromagnetic induction is the production of induced current in a coil placed in a region where the magnetic field changes with time. Reason (R) : Electric motor utilises the phenomenon of electromagnetic induction.

    A
    Both (A) and (R) are true and (R) is correct explanation of the assertion
    B
    Both (A) and (R) are true but (R) is not the correct explanation of the assertion.
    C
    (A) is true but (R) is false.
    D
    (A) is false but (R) is true.

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    Explore conceptually related problems

    Answer question numbers (a)-(d) on the basis of your understanding of the following paragraph and the related studied concepts : The phenomenon of electromagnetic induction is the production of induced current in a coil placed in a region where the magnetic field changes with time. The magnetic field may change due to a relative motion between the coil and a magnet placed near to the coil. If the coil is placed near to a current carrying conductor, the magnetic field may change either due to a change in the current through the conductor or due to the relative motion between the coil and conductor. The direction of the induced current is given by the Fleming's right-hand rule. Name a practical device based on the phenomenon of electromagnetic induction.

    State Lenz's law of electromagnetic induction. The magnetic threading of'a coil changes from 12 xx 10^(-3) Wb to 6 xx 10^(-3) Wb in 0.01 second. Calculate the induced emf.

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    Electromagnetic brakes work on the principle of electromagnetic induction. If a metallic disc or a coil is rotating in a uniform magnetic field, it will experience a torque due to induced currents set up in the disc. According to Lenz's law, induced current is in a direction so as to oppose the rotation. Hence a retarding torque is produced. The rotating wheel of a vehicle is connected to a coil placed in a uniform emf is used to charge a battery. Thus kinetic enery of wheel is stored as chemical energy. The drawback of electromagnetic brake is that induced current or retarding torque is directly proportional to speed of rotation. The speed, therefore, decays exponentially and vehicle will take a long time to stop. Thus, mechanical brakes are used simultaneously. The working of electromagnetic brakes does not involve

    Electromagnetic brakes work on the principle of electromagnetic induction. If a metallic disc or a coil is rotating in a uniform magnetic field, it will experience a torque due to induced currents set up in the disc. According to Lenz's law, induced current is in a direction so as to oppose the rotation. Hence a retarding torque is produced. The rotating wheel of a vehicle is connected to a coil placed in a uniform emf is used to charge a battery. Thus kinetic enery of wheel is stored as chemical energy. The drawback of electromagnetic brake is that induced current or retarding torque is directly proportional to speed of rotation. The speed, therefore, decays exponentially and vehicle will take a long time to stop. Thus, mechanical brakes are used simultaneously. The advantage of electromagnetic brakes is that

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