Question

mention under which condition the charges can move in the circuit and name the device which is used to maintain the this condition

Answer 1

Charges can move if there is a difference of electric pressure or potential difference along the
conductor. Electric cell or a battery consisting of two or more cells.

Answer 2

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Charge can move in a conductor only when a potential difference is maintained between it's ends .

A cell or a battery is used to maintain potential difference and hence , there is a flow of electric charges in an electric circuit .

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