The number density of free electrons in copper is nearly $8 \times 10^{28}$ m$^{-3}$. A copper wire has its area of cross section = $2 \times 10^{-6}$ m$^2$ and is carrying a current of 3.2 A. The drift speed of the electrons is __________ $\times 10^{-6}$ ms$^{-1}$

JEE Main 2023 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 8 April 2023, Shift 2, Physics Q60

Question 60 of 90 in this shift, Physics question 30 of 30, Section B.

The number density of free electrons in copper is nearly

8 \times 10^{28}

^{-3}

. A copper wire has its area of cross section =

2 \times 10^{-6}

^2

and is carrying a current of 3.2 A. The drift speed of the electrons is __________

\times 10^{-6}

^{-1}

Official answer

125

NTA final key.

Chapter: Current Electricity
Topic: Ohm's Law and Resistance
Idea tested: Drift Velocity and Current

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.