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Question
A potential difference (V) is applied across a conductor of length 'L' and cross-sectional area 'A'.
How will the drift velocity of electrons and the current density be affected if another identical conductor of the same material were connected in series with the first conductor? Justify your answers.
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Solution
We know,
Drift velocity, `v_d = (eE)/mtau ⇒ (eV)/(mL)tau`
Current density, J = `I/A`
If another conductor of the same length will be connected in series. I will remain the same and my potential will become half. So, drift velocity will become half and current density will remain the same.
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