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Drift speed of electrons, when 1.5 A of current flows in a copper wire of cross section 5 mm 2 , is v. If electron density in copper is 9 × 10 28 /m 3 the value of v in mm/s is close to ( Take charge of electron to be = 1.6 × 10 –19 C )

1. 0.02
2. 0.2
3. 3
4. 2

Correct answer: 0.02

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