Question

The radius of the thin wire is 0.22 mm, and the radius of the thick wire is 0.66 mm. There are 4e+28 mobile electrons per cubic meter of this material, and the electron mobility is 0.0006 (m/s)/(V/m). If 3e+18 electrons pass location D each second, how many electrons pass location B each second? Correct: Your answer is correct. electrons per second What is the magnitude of the electric field at location B?

Answer 1

Radius of thin wire, r = 0.22 times 10^-3m Radius of thick wire, R = 0.66 xl0^-3m No.of electrons passing through B, N = 3 times l0^18electrons Electron mobility, mu = 0.0006(m/s)/(V/m) Electric field at location B, E = v_d/mu Drift velocity, v_d = I/neA Hence, E = I/NEA = Ne/t/mune times piR^2 = 3 times 10^18/0.0006 times 4 times 10^28 times 3.14 times (0.66 times 10^-3)^2 = 0.0914 V/m