A wire has a cross-sectional area of 0.10 mm².If there are 4.0 × 10²⁸ atoms per cubic meter in this wire,and if each atom contributes 2 free electrons,what is the drift velocity of the electrons when the current in the wire is 6.0 A? (e = 1.60 × 10^-19 C) A) 0.0047 m/s B) 0.0092 m/s C) 0.94 m/s D) 0.019 m/s

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Quizplus · Accepted Answer

The drift velocity $v_d$ can be calculated using the formula $v_d = \frac{I}{nAe}$, where $I$ is the current, $n$ is the number of free electrons per unit volume, $A$ is the cross-sectional area, and $e$ is the charge of an electron. Given $I = 6.0 \, \text{A}$, $n = 2 \times 4.0 \times 10^{28} \, \text{electrons/m}^3$ (since each atom contributes 2 free electrons), $A = 0.10 \times 10^{-6} \, \text{m}^2$, and $e = 1.60 \times 10^{-19} \, \text{C}$, substituting these values into the formula gives a drift velocity of approximately $0.0047 \, \text{m/s}$.

A Wire Has a Cross-Sectional Area of 0