Home
Class 12
PHYSICS
A coil of inductance L = 2.0 mu H and...

A coil of inductance `L = 2.0 mu H` and resitance `R = 1.0 Omega` is connected to a source of constant `emf E = 3.0 V`. A resistance `R_(s) = 2.0 Omega` is connected in parallel with the coil. Find the amount of heat generated in the coil after the swich `Sw` is disconnecied. The internal resistance of the source is negligible.

Text Solution

Verified by Experts

Inilally, after a steady current is set up, the current is flowing as shown.
In steady condition `i_(20) = (xi)/(R). i_(10) = (xi)/(R_(0))`.
When the swich is disconnected, the current through `R_(0)` changes from `i_(10)` to the right, to `i_(20)` to the left.(The current in the inducatance cannot suddenly.). We have have the equaction,
`L = (di_(2))/(dt) + (R + R_(0)) i_(0) = 0`
This equaction has the solution `i_(2) = i_(20) e^(-t(R + R_(0))//L)`
The heat dissipated in the coil is, `Q = int_(0)^(oo) i_(2)^(2) R dt = i_(20)^(2) R int_(0)^(oo) e^(-2t(R + R_(0))//L) dt`
`= R i_(20)^(2) xx (L)/(2(R + R_(0))) = (L xi^(2))/(2R (R + R_(0))) = 3 mu J`
Promotional Banner

Topper's Solved these Questions

  • ELECTRODYNAMICS

    IE IRODOV, LA SENA & SS KROTOV|Exercise Motion Of Charged Particle In Magnetic Field|36 Videos
  • ELECTRODYNAMICS

    IE IRODOV, LA SENA & SS KROTOV|Exercise Constant Magnetic Fiels - Magnetics|69 Videos
  • ELECTRICITY AND MAGNETISM

    IE IRODOV, LA SENA & SS KROTOV|Exercise All Questions|6 Videos
  • ELECTROMAGNETISM

    IE IRODOV, LA SENA & SS KROTOV|Exercise All Questions|24 Videos

Similar Questions

Explore conceptually related problems

A coil of inductance L=50muH and resistance = 0.5Omega is connected to a battery of emf = 5V. A resistance of 10Omega is connected parallel to the coil. Now, at the same instant the connection of the battery is switched off. Then, the amount of heat generated in the coil after switching off the battery is

A coil =of inductance L=50muH and resistance = 0.5Omega is connected to a battery of emf=5A. A resistance of 10Omega is connected parallel to the coil. Now at some instant the connection of the battery is switched off. Then the amount of heat generated in the coil after switching off the battery is (0.02)x in mJ. Find valuie of x.

A coil of inductance L = 300 mH and resitance R = 140 m Omega is connected to a constant voltage source. How soon will the coil current reach eta = 50 % of the steady-state value ?

A coil of inductance 8.4 mH and resistance 6 (Omega) is connected to a 12 V battery. The current in the coil is 1.0 A at approximately the time

A coil of inductance 8.4 mH and resistance 6 Omega is connected to a 12 V battery. The current in the coil is 1.0 A at approximately the time.

A coil o finductanc e 8.4mH and resistance 6Omega is connected to a 12V battery. The current in the coil is 1.0A in the time (approx .)

A coil of inductance L=0.2 H and of resistance R= 62.8 Omega is connected to the mains alternating voltage of frequency 50Hz. What can be the capacitance of the capacitor connected in series with the coil if the useful power has to remain unchanged?

IE IRODOV, LA SENA & SS KROTOV-ELECTRODYNAMICS-Electromagnetic Induction
  1. Find the appoximate formula expressing the mutual inductance of tw...

    Text Solution

    |

  2. There are two stationary loops with mutual inductance L(12). The curr...

    Text Solution

    |

  3. A coil of inductance L = 2.0 mu H and resitance R = 1.0 Omega is c...

    Text Solution

    |

  4. An iron tor suports N = 500 turns. Find the magnetic field energy ...

    Text Solution

    |

  5. An iron core shaped as a doughnut with round cross-section of radiu...

    Text Solution

    |

  6. A thin ring made of magnetic has a mean diameter d = 30 cm and sup...

    Text Solution

    |

  7. A long cylinder of radius a carrying a unifrom surface charge rot...

    Text Solution

    |

  8. At what magnetic of the electric field srength in vacumm the vol...

    Text Solution

    |

  9. A thin uniformly charged ring of radius a = 10 cm rotates about its...

    Text Solution

    |

  10. Using the expression for volume density of magnetic eneregy, demons...

    Text Solution

    |

  11. Two indentical coils, each of inductance L, are interconnected (a) in...

    Text Solution

    |

  12. Two solenoids of equal length and almost equal cross-sectional ...

    Text Solution

    |

  13. Demonstarate that the magnetic energy of interaction of two current...

    Text Solution

    |

  14. Find the interaction energy of two loops carrying currents I(1) and...

    Text Solution

    |

  15. The space between two concentric metallic spheres is filled up with ...

    Text Solution

    |

  16. A parallel plate capcitor is formed by two discs with a unifrom p...

    Text Solution

    |

  17. A parallel plate air condenser whose each plate has an area S = ...

    Text Solution

    |

  18. The space between the electrodes of a parallel-plate capacitor is fil...

    Text Solution

    |

  19. A long straight solenoid has n turns per unit length. An alternatin...

    Text Solution

    |

  20. A point charge q moves with a non-relatives velocity v = const. Find ...

    Text Solution

    |