Asteady voltage source v = 1 v is connected to a coil which consists of a 50 m length of copper wire of radius 0.01 mm. given that the number density of mobile electrons in copper is 8.5 x 1022 cm-3 and p= 1.72 x 10-82 m, calculate: (a) the electric field e which acts on the mobile electrons in the coil. (b) the drift velocity v of the mobile electrons. (c) the resistance r of the coil. (d) the steady dc current i in the coil. (ans: 0.02 v m-! ; 8.6 x 10-5 m sl; 2738 w; 0.36 ma)