AP EAMCET · PHYSICS · Current Electricity
A constant potential difference is applied between the ends of the wire. If the length of the wire is elongated 4 times, then the drift velocity of electrons will be
- A increases \(4\) times
- B decreases \(4\) times
- C increases \(2\) times
- D decreases \(2\) times
Answer & Solution
Correct Answer
(B) decreases \(4\) times
Step-by-step Solution
Detailed explanation
\(v_d \propto \frac{1}{l} \frac{v_{d_1}}{v_{d_2}}=\frac{I_1}{I_2}=\frac{4 I}{I} \Rightarrow v_{d_2}=\frac{v_{d_1}}{4}\) So drift velocity will decrease by 4 times
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