Page 712 - SUBSEC October 2017_Neat
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                    (e)    Describe the motion of the free electrons in a metallic conductor

                             (i)   before the current is switched on
                            (ii)   after the current is turned on.

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                    (f)    Using your answers to (e) (i) and (e) (ii), explain the meaning of the term ‘drift
                           velocity’.


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                                                                                             I
                    (g)    Show that the drift velocity in a metallic conductor is given by v =   neA     where n is

                           the electron charge density, e is the electron charge, I is the current and A is the cross-
                           sectional area of the conductor.

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