Question

Q2a) An 0.80-mm-diameter wire made from a metal alloy (mixture of different metals), has a conductivity that changes with distance from the center as: o(r) = 0,+ ar where s0 = 4.5 x 107 Q1 m1 C = 2.3 x 1011 22-1 m 2 What is the resistance of a 15-foot piece of this wire? (1 ft +0.305 m). Give your answer to two significant figures, with the units. Q2b) What is the resistivity (p) of this 0.80 mm thick, 15-foot-long wire? Give your answer to two significant figures, with the units

Answer 1

och = 00 + 20 limen 0o = 45x107, C = 2.3x2011 ha rz 0-80 mm - 0.4x103 48104 2 Then oln = 4.58107 + 2x 2.3x10 lx 4x10-4 3.14 ¥ 45*107 + (S. 85) Xo7 oln = 10.36820) Resistance Rall pal - 15 Foot Isxo. 35 = 9.50 A = 2 = 314x44x164) = 50.24x108 R = 4.575 4.575 X16 10.36X 107 X 50.24x108 10.36x50.24 R = 45.75 ? 0.8780 $20:49 Renistivity is at - I - Conductivity P = Torx 0.96 e - 0.965X168 A-CMNM