Home
Class 12
PHYSICS
A charged capacitor is allowed to disch...

A charged capacitor is allowed to dischare through a resistor by closing the key at the instant `t=0`. At the instant `t=(ln 4)mus`, the reading of the ammeter falls half the initial vaslue. The resistance of the ammeter is equal to

A

`0.5Omega`

B

`1Omega`

C

`2Omega`

D

`4Omega`

Text Solution

Verified by Experts

The correct Answer is:
C
The given time is the half life time of the exponentially decreasig eqution.
`:. t=t_(1/2)=(ln 2)tau_C=(ln 2)CR_(n et)`
`:. R_(n et)=t/((ln 2)C)`
`=(2(ln 2)mus)/((ln 2)(0.5muF))=4Omega`
`:.` Resistance of ammeter `=2Omega`
Promotional Banner

Topper's Solved these Questions

  • CAPACITORS

    DC PANDEY ENGLISH|Exercise OBJECTIVE_TYPE|1 Videos

  • CAPACITORS

    DC PANDEY ENGLISH|Exercise OBJECTIVE_TYPE|1 Videos

  • ATOMS

    DC PANDEY ENGLISH|Exercise MEDICAL ENTRANCES GALLERY|42 Videos

  • COMMUNICATION SYSTEM

    DC PANDEY ENGLISH|Exercise Subjective|11 Videos

Similar Questions

Explore conceptually related problems

A charged capacitor is allowed to discharged through a resistor 2 Omega by closing the switch K at the t=0 . At time t = 2 mus , the reading of the falls half of its initial value. The resistance of ammeter is equal to

In the circuit shown the key (K) is closed at t=0 , the current through the key at the instant t=10^-3 ln, 2 is

An ammeter and a voltmeter are initially connected in series to a battery of zero internal resistance. When switch S_(1) is closed the reading of the voltmeter becomes half of the initial, whereas the reading of the ammeter becomes double. If now switch S_(2) is also closed, then reading of ammeter becomes :

Let C be the capacitance of a capacitor discharging through a resistor R. Suppose t_1 is the time taken for the energy stored in the capacitor to reduce to half its initial value and t_2 is the time taken for the charge to reduce to one-fourth its initial value. Then the ratio t_1//t_2 will be

A capacitor of capacitance 3muF is first charged by connecting it across a 10 V battery by closing key K_(1) . Then it is allowed to get discharged through 2 Omega and 4 Omega resistors by closing the key K_(2) . The total energy dissipated in the 4 Omega resistor is equal to

An uncharged capacitor is connected to an ideal battery through a resistance R and a switch S. Initially the switch is open . At an instant, the switch is closed . Taking this instant as t=0, which of the following graphs represent correct variation of the quantity taken along y -axis with time ?

In the given at t = 0 , switch S is closed. The current through the 10 Omega resistor at any instant t(0 lt t lt oo) will be

A capacitor of capacitance 5muF is charged to a potential difference 200 V and then allowed to dischage through a resistance 1kOmega . The cahrge on the capacitor at the instant the current through the resistance is 100 Ma, is (in muC ):

In the circuit shown in fig, the time constant of the two braches are equal(=T). Then if the key S is closed at the instant t=0, the time in which the current in the circuit through the battery will rise to its final value of (E//R) will be, (assume that the internal resistance of the battery and of the connecting wire are negligible)

A 4mu F capacitor is charged to 400 volts and then its plates are joined through a resistor of resistance 1K Omega . The heat produced in the resistor is

DC PANDEY ENGLISH-CAPACITORS-Exercise
  1. In the circuit diagram the current through the battery immediately aft...

    Text Solution

    |

  2. In the circuit shown switch S is closed at t=0. Let i1 and i2 be the c...

    Text Solution

    |

  3. A charged capacitor is allowed to dischare through a resistor by clos...

    Text Solution

    |

  4. Five identical capacitor plates are arranged such that they make four ...

    Text Solution

    |

  5. A capacitor of capacitance C is charged to a potential difference V fr...

    Text Solution

    |

  6. X and Y are large, parallel conducting plates close to each other. Eac...

    Text Solution

    |

  7. In the circuit shown in the figure, switch S is closed at time t=0. Se...

    Text Solution

    |

  8. An electrical circuit is shown in the given figure. The resistance of ...

    Text Solution

    |

  9. In the circuit shown, A and B are equal resistances. When S is closed,...

    Text Solution

    |

  10. A parallel plate capacitor is charged from a cell and then isolated fr...

    Text Solution

    |

  11. In the circuit shown each capacitor has a capcitance C. The emf of the...

    Text Solution

    |

  12. Two capacitors of 2muF and 3muF are charged to 150 V and 120 V, respec...

    Text Solution

    |

  13. A parallel plate capacitor is charged and then the battery is disconne...

    Text Solution

    |

  14. A capacitor of 2F (practically not possible to have a capacity of 2F) ...

    Text Solution

    |

  15. given that potential differene across 1muF capacitor is 10V. Then,

    Text Solution

    |

  16. The capacitor C1 in the figure shown initially carries a charge q0. Wh...

    Text Solution

    |

  17. The capacitor C1 in the flgure shown initially carries a charge q0. Wh...

    Text Solution

    |

  18. Figure shows a parallel plate capacitor with plate area A and plate se...

    Text Solution

    |

  19. Figue shows a parallel plate capacitor with plate area A and plate sep...

    Text Solution

    |

  20. Five identical conducting plates, 1, 2,3,4 and 5 are fixed parallel pl...

    Text Solution

    |