Astraight, cylindrical wire lying along the x axis has a length l and a diameter d. it is made of a material described by ohm's law with a resistivity rho. assume potentialv is maintained at the left end of the wire at x = 0. also assume the potential is zero at x = l. in terms of l, d, v, rho, and physical constants, derive expressions for the following. (use the following as necessary: l, d, v, rho, and π.)

(a) the electric field in the wire

magnitude
direction +i -i +j -j +k -k

(b) the resistance of the wire
r =

(c) the electric current in the wire

magnitude
direction +i -i +j -j +k -k

(d) the current density in the wire

magnitude
direction +i -i +j -j +k -k