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Question
A current passes through a resistor. Let K1 and K2 represent the average kinetic energy of the conduction electrons and the metal ions, respectively.
Options
K2 < K2
K1 = K2
K1 > K2
Any of these three may occur
Solution
K1 > K2
The metal ions are bound at their positions and vibrate due to collisions with electrons and due to thermal energy. The conduction electrons are free to move. They get energy from the electric field set inside the conductor by connection with a battery and due to thermal motion. The velocity of the electrons is high.
Thus, the kinetic energy of the electrons is greater than the kinetic energy of the metal ions.
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