$A$ large number of free electrons are present in metals,yet no current flows in the absence of electric potential across it. Explain the statement with reason.
(N/A) In metals,free electrons are in a state of random thermal motion. In the absence of an external electric field,the average velocity of these electrons in any given direction is zero,meaning there is no net flow of charge. Current is defined as the rate of flow of charge. For a net flow to occur,an external electric potential difference must be applied across the conductor. This potential difference creates an electric field that exerts a force on the electrons,causing them to drift in a specific direction,thereby establishing an electric current.
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