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An inductor coil stores 64J of magnetic field energy nad dissipates energy at the rate of 640W when a current of 8A is passed through it. If this coil is joined across an ideal battery, find the time constant of the circuit in seconds:

Option 1 -

0.8

Option 2 -

0.2

Option 3 -

0.125

Option 4 -

0.4

0 2 Views | Posted 2 months ago
Asked by Shiksha User

  • 1 Answer

  • V

    Answered by

    Vishal Baghel | Contributor-Level 10

    2 months ago
    Correct Option - 2


    Detailed Solution:

    U B = 1 2 L l 2 . . . . . . . . . . . . ( i )

    PR = l2R

    => 640 = (8)2 R

    R = 1 0 Ω

    from (i) 64 = 1 2 × L × ( 8 ) 2

    L = 2H

    l = L R = 2 1 0 = 0 . 2     s e c o n d        

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