(Solved): A copper wire has a square cross section 2.3mm on a side. The wire is 4.5m long and carries a c ...

A copper wire has a square cross section $2.3\mathrm{mm}$ on a side. The wire is $4.5\mathrm{m}$ long and carries a current of $3.4\mathrm{A}$. The density of free electrons is $8.5\times 10^{28}{\mathrm{m}}^{?3}$. Find the magnitude of the current density in the wire. Express your answer using two significant figures. Part B Find the magnitude of the electric field in the wire. Express your answer using two significant figures. How much time is required for an electron to travel the length of the wire? Express your answer using two significant figures.