Question

Estimate the drift velocity and current density in a copper wire of thickness 2mm, carrying a conductor current of 5A.

Answer 1

Answer:

42704 m/s.

Explanation:

Current, I = 5A

Wire thickness = 2mm

So, the cross sectional area of the wire, A = π * r ²

                                                                 = π * 1 ²

                                                                 = 3.14 mm²

                                                                 = 3.14 / 10⁶ m²

We know, for copper n = 8.5 x 10²⁸  per m³.

The charge of an electron, Q = 1.6 x 10⁻¹⁹ C

So, I = n A v Q, where v is the drift velocity.

   or, v = I/(n*A*Q)

   or, v = 5 / (8.5x 10²⁸ * 3.14 x 10⁻⁶ * 1.6 x 10⁻¹⁹)

   or, v = 42704 m/s