Question

Computer electrical conductivity of a Cylindrical silicone specimen 10 mm in diameter and 60 mm in length in which a current of .25 A’s passes in an axial direction. A voltage of 24 V is measured across to probes that are separated by 45 mm. Compute the resistance over the entire 60 mm of the specimen. If the SI specimen has a carrier concentration of 1.5×10^10 m^-3, what is the electron mobility?

Answer 1

Use Microscopic Ohm's law

=>

=>

this is the conductivity

Now, resistance of the specimen will be:

Electron mobility is related to conductivity and carrier density by the relation:

so, the electron mobility will be:

.