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A wire whose cross sectional area is inc...

A wire whose cross sectional area is increasing linearly from its one end to the other, is connected across of battery of V volts.Which of the following quantities remain constant in the wire?
a) drift speed b) current density c) electric current d) electric field

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The electric current remains constant in the wire so that no charge accumulates in the wire. The drift speed and current density depends on the area of cross section and hence they do not remain constant. From the relation `j=sigma E`, it can be deduced that the electric field does not remain constant.
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