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Question
If potential difference between the two ends of a metallic wire is doubled, drift speed of free electrons in the wire ______.
Options
Remains same.
Becomes double.
Becomes four times
Becomes half
Solution
If potential difference between the two ends of a metallic wire is doubled, drift speed of free electrons in the wire becomes double.
Explanation:
Drift velocity `= v_d = (eVτ)/(ml)`
When V is Potential difference
According to question, V = 2V
Then `v_d = (2eVτ)/(ml)`
= `2v_d`
Hence, drift velocity also becomes double.
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