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    Im having trouble with electron drift velocity,
    How would you solve this for example, what's the step by step method
    A copper wire has a cross sectional area of 2.0mm^2 &carries a current of of 6.0A
    Calculate mean drift velocity of electrons in wire
    # density of copper atoms =8.0 x 10^28
    Each copper atom provides one conduction electron
    Charge on electron: -1.6x10^-19 C

    PLEASE GO THROUGH EACH STEP AND EACH FORMULA USED!
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    I=nvQA

    I is current in Amps

    n is the number density of charge carriers... in a metal you can use the number density of metal atoms multiplied by the number of conduction electrons provided by each atom

    v is the drift velocity of the charge carriers

    Q is the amount of charge carried by each charge carrier... if the charge carriers are electrons this is the charge per electron

    A is the cross sectional area in m2

    so you've got to rearrange I=nvQA to get v on it's own on one side of the equals sign... not forgetting to convert any units necessary before you start calculating.

    note - the drift velocity is usually lower than you expect when you first start calculating them
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    (Original post by Joinedup)
    I=nvQA

    I is current in Amps

    n is the number density of charge carriers... in a metal you can use the number density of metal atoms multiplied by the number of conduction electrons provided by each atom

    v is the drift velocity of the charge carriers

    Q is the amount of charge carried by each charge carrier... if the charge carriers are electrons this is the charge per electron

    A is the cross sectional area in m2

    so you've got to rearrange I=nvQA to get v on it's own on one side of the equals sign... not forgetting to convert any units necessary before you start calculating.

    note - the drift velocity is usually lower than you expect when you first start calculating them
    n=(8×10^28)×no. Of conduction electrons provided by each electron
    But how do I find # conduction electrons?
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    (Original post by SamuraiMK)
    n=(8×10^28)×no. Of conduction electrons provided by each electron
    But how do I find # conduction electrons?
    the equation works off number density, the number per m3

    it's a property of the material the conductor is made of - not it's size or shape
 
 
 
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