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Velocity electromagnetics?
A current with magnitude of 1amps flows in a wire which has a circular cross section with a radius of 1mm. Concentration of electrons in the wire is 8*10^28 electrons/m3. Find the mean velocity of electrons in the wire.
1 Answer
- Steve4PhysicsLv 79 years agoFavorite Answer
The standard formula is
I = nqvA
so v= I/(nqA)
where
I = 1A
n = 8*10^28 electrons/m3
q = 1.6*10^-19 C (chargge on electron)
A = cross sectional area = πr² = π(0.001)² (becnasue 1mm = 0.001m)
Just plug the values in to work out v in m/s.
