Home
Class 12
PHYSICS
There is a current of 40 ampere in a wir...

There is a current of 40 ampere in a wire of `10^(-6)m^(2)` are of cross-section. If the number of free electron per `m^(3)` is `10^(29)` then the drift velocity will be

Text Solution

Verified by Experts

The correct Answer is:
A
Thrust `= F = rhoAv^(2) " " [A = pir^(2)]`
at equilibrium `rhoAv^(2) = mg`
Power `P = Fv = rhoAv^(3)`
`= (mg)/(r ) sqrt((mg)/(p pi))`
Promotional Banner

Topper's Solved these Questions

  • CURRENT ELECTRICITY

    ALLEN |Exercise EXERCISE-IV A|32 Videos

  • CURRENT ELECTRICITY

    ALLEN |Exercise EXERCISE-IV B|14 Videos

  • CURRENT ELECTRICITY

    ALLEN |Exercise EX.II|66 Videos

  • CIRCULAR MOTION

    ALLEN |Exercise EXERCISE (J-A)|6 Videos

  • GEOMETRICAL OPTICS

    ALLEN |Exercise subjective|14 Videos

Similar Questions

Explore conceptually related problems

In one atom of As is added per 10^(3) atoms of Ge then the number of free electron in one mole of Ge will be ……..

If 2×10^(6) electrons/s are flowing through an area of cross section of 2×10^(-4) m^(2) then the current will be:-

If 10^(6) electrons/s are flowing through an area of cross section of 10^(-4) m^(2) then the current will be:-

A copper wire has a square cross-section, 2.0 mm on a side. It carries a current of 8 A and the density of free electrons is 8 xx 10^(28)m^(-3) . The drift speed of electrons is equal to

If 2 ×10^(6) electrons/s are flowing through an area of cross section of 10^(-4) m^(2) then the current will be:-

A silver wire 1mm diameter carries a charge of 90 coulombs in 1 hours and 15 minutes. Silver contains 5.8xx10^(28) free electrons per cm^(3) find the current in wire and drift velocity of the electron.

Cross-sectional area of a Copper wire is equal to area of a square of length 2 mm. If this copper wire draws 8 A electric current, then find the drift velocity of free electron. Number density of electron in Copper wire is 8 xx 10^(28) m^(-3)

Free electron number density in one wire is n, its area of cross-section is A, and drift velocit of electrons is v_(d) Then electric current forme in this wire is ......

Every atom makes one free electron in copper. If 1.1 ampere current is flowing in the wire of copper having 1 mm diameter, then the drift velocity (approx.) will be (Density of copper =9 xx 10^(3) kg m^(-3) and atomic weight = 63)

The current in the primary circuit of a potentiometer wire is 0.5 A. Specific resistance of wire is 4 xx 10^(-7) Omega m and area of cross section of wire is 8 xx 10^(-6) m^(2) . The potential gradient on the wire would be

ALLEN -CURRENT ELECTRICITY-EXERCISE-III
  1. Two cells , each of emf E and internal resistance r, are connected in ...

    Text Solution

    |

  2. In a network as shown in the figure the potential difference across th...

    Text Solution

    |

  3. There are 8.4xx10^(22) free electrons per cm^(3) in copper. The curren...

    Text Solution

    |

  4. In a typical wheatstone network the resistance in cyclic order are A=1...

    Text Solution

    |

  5. In the circuit shown below, the power developed in 6Omega resistor is ...

    Text Solution

    |

  6. A potentiometer having the potential gradient of 2 mV//cm is used to m...

    Text Solution

    |

  7. A microammeter has a resistance of 100W and a full scale range of 50 µ...

    Text Solution

    |

  8. In the circuit shown here, what is the value of the unknown resistor R...

    Text Solution

    |

  9. A battery has e.m.f. 4 V and internal resistance r . When this battery...

    Text Solution

    |

  10. In the circuit shown here, E(1) = E(2) = E(3) = 2 V and R(1) = R(2) = ...

    Text Solution

    |

  11. AB is a potentiometer wire of length 100cm and its resistance is 10ohm...

    Text Solution

    |

  12. Three resistance of values 2Omega,3Omega and 6Omega are to be connect...

    Text Solution

    |

  13. A battery of electro motive force E is connected in series with a resi...

    Text Solution

    |

  14. Two resistance wires on joining in parallel the resultant resistance i...

    Text Solution

    |

  15. The temperature coefficient of resistance of a wire is 0.00125 per .^...

    Text Solution

    |

  16. If specific resistance of a potentiometer wire is 10^(–7 ) Omega m, th...

    Text Solution

    |

  17. The resistance of each arm of the wheat stone bridge is 10Omega. A r...

    Text Solution

    |

  18. Copper and silicon is cooled from 300 K to 60 K, the specific resistan...

    Text Solution

    |

  19. There is a current of 40 ampere in a wire of 10^(-6)m^(2) are of cross...

    Text Solution

    |

  20. An ammeter and a voltmeter are joined in sereis to a cell. Their readi...

    Text Solution

    |