Home
Class 12
PHYSICS
A current 4.0 A exist in a wire of cross...

A current 4.0 A exist in a wire of cross-sectional area `2.0 mm^(2)`. If each cubic metre of the wire contains `12.0xx10^(28)` free electrons, then the drift spped is

A

`6.0xx10^(28) m^(-3)`

B

`3.6xx10^(29) m^(-3)`

C

`7.0xx10^(30) m^(-3)`

D

`8.2xx10^(32) m^(-3)`

Text Solution

Verified by Experts

The correct Answer is:
A
We know that, the current of the wire,
`i="neAv"_(d)`
`rArr " " 4=nxx1.6xx10^(-19)xx2xx10^(-6)xx2.1xx10^(-4)`
The number of free free electrons
or `n=6.0xx10^(28)m^(-3)`
Promotional Banner

Topper's Solved these Questions

  • CURRENT ELECTRICITY

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise EXERCISE 2|26 Videos

  • CURRENT ELECTRICITY

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise MHT CET CORNER|32 Videos

  • CURRENT ELECTRICITY

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise MHT CET CORNER|32 Videos

  • COMMUNICATION SYSTEM

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise MHC CET Corner|6 Videos

  • ELASTICITY

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise MHT CET CORNER|16 Videos

Similar Questions

Explore conceptually related problems

A current of 2 A is flowing through a wire of length 4 m and cross-sectional area 1 mm^(2) . If each cubic metre of the wire contains 10^(29) free electrons, find the average time taken by an electron to cross the length of the wire.

Consider a wire of length 4m and cross-sectional areal 1 mm^(2) carrying of 2A. If each cubic metre of the material contains 10^(29) free electrons, find the average time taken by an electron to cross the length of the wire.

A current of 1.34A exists in a copper wire of cross-section 1.0mm^(2) . Assuming eac copper atom contributes one free eectron. Calculate the drift speed of the free electrons in the wire. The density of copper is 8990 kg// m^(3) and atom ic mass=63.50.

The current in a metal wire of cross-sectional area 10^(-6)m^(2) is 1.6A .If the free electron density of the metal is 8times 10^(28)m^(-3) then the drift speed of electrons is

A current of 4.8 A is flowing in a copper wire of cross-sectional area 3xx10^(-4) m^(2) . Find the current density in the wire.

A current of 3 A is flowing through a wire of length 2 m and cross- sectional area 1mm^(2) . If wire contains 10^(29) "electrons"//m^(3) , calculate the average time taken by an electron to cross the length of the wire.

A current of 10 A exists in a wire of crossectional area of 5 m m^(2) with a drift velocity of 2 xx 10^(-3) ms^(-1) . The number of free electrons in each cubic meter of the wire is "___________"

There is a current of "4.0A" in a wire of cross-sectional area 10^(-6)m^(2) .If the free electron density in wire is 10^(28)m^(-3) ,the drift velocity is :

A current of 1.0 A exists in a copper wore of cross-section 1.0mm^(2) .Assuming one free electron per atonm calculate the drift speed of the free electrons in the wire.The density of copper is 9000kgm^(-3) .

There is a current of 0.21 A in a copper wire of area of cross section 10^(-6)m^(2) . If the number of electrons per m^(3) is 18.4xx10^(28) then the drift velocity is ( e=1.6xx10^(-19)C )

MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS-CURRENT ELECTRICITY-EXERCISE 1
  1. Electric field (E) and current density (J) have relation

    Text Solution

    |

  2. The temperature (T) dependence of resistivity (rho) of a semiconductor...

    Text Solution

    |

  3. A current 4.0 A exist in a wire of cross-sectional area 2.0 mm^(2). If...

    Text Solution

    |

  4. A wire of resistance R is elongated n-fold to make a new uniform wire....

    Text Solution

    |

  5. The four colours on a resistor are: brown, yellow, green and gold as r...

    Text Solution

    |

  6. The resistance will be least in a wire with length, cross-section area...

    Text Solution

    |

  7. A wire has resistance of 10Omega. If it is stretched by 1/10th of its ...

    Text Solution

    |

  8. If resistivity of copper conductor is 1.7xx10^(-8) Omega -m and electr...

    Text Solution

    |

  9. A wire is stretched so as to change its diameter by 0.25% . The percen...

    Text Solution

    |

  10. A potential difference of 100 V is applied to the ends of a copper wir...

    Text Solution

    |

  11. If power dissipated in the 9 Omega resistor in the resistor shown is 3...

    Text Solution

    |

  12. The effective resistance between points A and C for the network shown ...

    Text Solution

    |

  13. A resistor of 6k Omega with tolerance 10% and another resistance of 4k...

    Text Solution

    |

  14. In the circuit given E = 6.0 volt, R(1) = 100Omega, R(2) = R(3)=50Omeg...

    Text Solution

    |

  15. The circuit in figure, where there are three resistors R(1),R(2) and R...

    Text Solution

    |

  16. The resistance across R and Q in the figure is

    Text Solution

    |

  17. Two resistances are joined in parallel whose equivolent resistance is ...

    Text Solution

    |

  18. The equivalent resistance of two resistors connected in series 6Omega ...

    Text Solution

    |

  19. Three resistances 2 Omega, 3 Omega and 4 Omega are connected in parall...

    Text Solution

    |

  20. Four resistances are connected in a circuit in the given figure. The e...

    Text Solution

    |