Question

хс Remaining Time: 09 minutes. 53 seconds Question completion Status What is the resistance of an Aluminum transmission line of length 3 km that has a cross sectional area of 3.14x10 *m? at temperature of 30°C Table 18.1 Resistivities and Temperature Coefficients at 20°C ρ (Ω-m) Conductors Silver Copper Gold wse the data in the table below Aluminum Tungsten Iron Lead Platinum Manganin Constantan Mercury Nichrome 1.59 x 10-* 1.67 x 10 2.35 x 10- 2.65 x 10- 5.40 x 108 9.71 x 10 21 x 10 10.6 x 10-8 44 x 10 49 x 10- 96 x 108 108 x 10 a(C) ρ (Ω·m) ac' Semiconductors (pure) 3.8 x 10 Carbon 3.5 x 10 -0.5 x 10 4.05 x 10 Germanium 0.6 -50 x 10-2 3.4 x 10 Silicon 2300 - 70 x 10 3.9 x 10 4.50 x 10- 5.0 x 10 Insulators 3.9 x 10' Glass 10" - 10 3.64 x 10 Lucite 0.002 x 10 Quartz (fused) 0.002 x 10 Rubber (hard) 1013 - 1016 0.89 x 10' Teflon 0.4 x 10 Wood 108 - 10" > 101 > 1016 > 101 Ć er

Answer 1

conductor. Resistivity 4 temperature relation for P = 2(lta (T-To)) Given Sn = 2.658108 x23.9x103 = 2000 at Ta foc 3 = 2.65 x108(1+3.9%10*3(80-203) S = 3.278 108 som Resistance دی ۸۵ Rase 3 x 10 R- 3.27x108 x 3.14x104 R = 0.31 2 Aus