Following are the text from an Electrical Engineering Textbook.
"it is seen that contrary to the common but mistaken view,
1. the electron drift velocity is rather very slow
2. is independent of the current flowing
3. independent of the area of the conductor"
first point can be explained by following example,
Assuming a normal current density J= 1.55 x 10^6 A/m^2, n=10^29 for copper conductor and e= 1.6 x 10^-19 coulomb, current density is given by,
J= n.e.v ampere/meter^2, where n is electron density per m^3, e is electron charge and v is drift velocity
we get v=.58 cm/min
However regarding point 2 and 3 above, I am not able to come to any concrete logic.
An enlightenment regarding above two point is highly appreciated.
"it is seen that contrary to the common but mistaken view,
1. the electron drift velocity is rather very slow
2. is independent of the current flowing
3. independent of the area of the conductor"
first point can be explained by following example,
Assuming a normal current density J= 1.55 x 10^6 A/m^2, n=10^29 for copper conductor and e= 1.6 x 10^-19 coulomb, current density is given by,
J= n.e.v ampere/meter^2, where n is electron density per m^3, e is electron charge and v is drift velocity
we get v=.58 cm/min
However regarding point 2 and 3 above, I am not able to come to any concrete logic.
An enlightenment regarding above two point is highly appreciated.
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