Assuming that there are 0.845 * 10²⁹ electrons per m³ in a wire with cross sectional area 69 mm² and drift velocity 4.12 * 10^-8 m/s,what is the density current in the wire?

Question

Quizplus · Accepted Answer

First, we need to calculate the current density (J) using the given values for charge carrier density (n), cross-sectional area (A), and drift velocity (v):
J = nAvq

where q is the charge of a single electron (1.6 x 10^-19 C).

Plugging in the given values:
J = (0.845 x 10^10 electrons/m^3) x (69 x 10^-6 m^2) x (4.12 x 10^-8 m/s) x (1.6 x 10^-19 C)

J = 557 A/m^2

Therefore, the answer is A.

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