Consider a wire of length 0.1 m with an area of cross section 1mm2 connected to 5 V. Find the current flowing through the metallic wire where μ=5×10−6m2v−1s−1,e=1.6×10−19C and n=8×1028m−3
3.2 A
4.2 A
5.6 A
32 A
E=Vl=50.1=50 Vm-1 ⇒I = neAVd = neAμE ∴ μ=Vd/E =8×1028×10−6×1.6×10−19×5×10−6×50=3.2 A