ConductorsWhen a potential difference of 115 V is applied between the ends of a
9.66-m-long wire, the current density is J = 1.42 A/cm2. Calculate
the conductivity of the wire material.
For a hypothetical electronic device, the potential difference DV,
measured across the device, is related to the current i by DV = (3.55 x
106 V/A2)i2. (a) Find the resistance
when the current is 2.40 mA. (b) At what value of the
current is the resistance equal to 16.0 W?
Calculate the mean free time t
between collisions for conduction electrons in aluminum at 20 C
using tables from the lecture. Each atom of aluminum contributes three
conduction electrons. The density of aluminum is 2.7 g/cm3 and it has
a molar mass of 27 g/mol.