(Solved): Aluminum has a resistivity of 2.65108m. An aluminum wire is 1.5m long and has a circula ...

Aluminum has a resistivity of $$2.65\times 10^{?8}??\mathrm{m}$$. An aluminum wire is $$1.5\mathrm{m}$$ long and has a circular cross section, but the diameter of the wire changes at its midpoint. The left half of the wire has a diameter of $$D_1=0.17\mathrm{mm}$$ while the right half has a diameter of $$D_2=0.28\mathrm{mm}$$. What is the resistance of this wire? (The total resistance is the sum of the resistance in each half.) A potential difference of $$1.25\mathrm{V}$$ is applied across the wire. What is the magnitude of the current density in the left half of the wire? What is the magnitude of the current density in the right half of the wire? What is the magnitude of the electric field in the left half of the wire? What is the magnitude of the electric field in the right half of the wire?