Determine the temperature at which the resistance of an aluminum wire will be twice its value at 20 degree celsius. (Assume its coefficient of resistivity remains constant.)

(a) A 35.5-m length of copper wire at 20.0°C has a radius of 0.23 mm. If a potential difference of 7.0 V is applied across the length of the wire, determine the current in the wire. (Use the values in the following table.) Resistivities and Temperature Coefficients of Resistivity for Various Materials (at 20°C) Material Silver A Copper Gold Aluminum Tungsten Iron Platinum Lead Nichrome a Carbon Germanium Silicon Glass Hard rubber Sulfur Quartz (fused) Resistivity (2. m) 1.59 x 107 1.7 x 10-8 2.44 x 10-8 2.82 x 10 5.6 x 107 10.0 x 10 11 x 10 -8 -8 0.46 -8 640 22 x 10-8 3.5 x 107 -8 -8 150 x 10- -8 -5 1010-1014 ≈1013 1015 75 x 1016 Temperature Coefficient of Resistivity [(°C)-¹] 3.8 x 10 -3 3.9 × 10-3 3.4 x 10-3 3.9 x 107 5.0 x 10 4.5 x 10-3 3.92 x 10 -3 -3 0.4 x 107 -3 3.9 × 10-3 -3 -3 -0.5 x 107 -48 x 10-3 -75 x 10-3 aA nickel-chromium alloy commonly used in heating elements. (b) If the wire is heated to 40.0°C while the 7.0-V potential difference is maintained, what is the resulting…

Suppose at 70°C the resistance of a platinum resistance thermometer is 170 Ω. When placed in aparticular solution, the resistance is 7+100 Ω. What is the temperature of this solution?Temperature Coefficient of resistivity for platinum is 3.93 x 10-3 1/ 0 C.

(a) A 35.1-m length of copper wire at 20.0°C has a radius of 0.23 mm. If a potential difference of 7.0 V is applied across the length of the wire, determine the current in the wire. (Use the values in the following table.) Resistivities and Temperature Coefficients of Resistivity for Various Materials (at 20°C) Material Resistivity(Ω · m) Temperature Coefficientof Resistivity [(°C)−1] Silver 1.59 ✕ 10−8 3.8 ✕ 10−3 Copper 1.7 ✕ 10−8 3.9 ✕ 10−3 Gold 2.44 ✕ 10−8 3.4 ✕ 10−3 Aluminum 2.82 ✕ 10−8 3.9 ✕ 10−3 Tungsten 5.6 ✕ 10−8 4.5 ✕ 10−3 Iron 10.0 ✕ 10−8 5.0 ✕ 10−3 Platinum 11 ✕ 10−8 3.92 ✕ 10−3 Lead 22 ✕ 10−8 3.9 ✕ 10−3 Nichromea 150 ✕ 10−8 0.4 ✕ 10−3 Carbon 3.5 ✕ 10−5 −0.5 ✕ 10−3 Germanium 0.46 −48 ✕ 10−3 Silicon 640 −75 ✕ 10−3 Glass 1010–1014   Hard rubber ≈1013   Sulfur 1015   Quartz (fused) 75 ✕ 1016   aA nickel–chromium alloy commonly used in heating elements.  ??A(b) If the wire is heated to 36.0°C while the 7.0-V potential difference is…

(a) A 34.9-m length of copper wire at 20.0°C has a radius of 0.29 mm. If a potential difference of 7.0 V is applied across the length of the wire, determine the current in the wire. (Use the values in the following table.) Resistivities and Temperature Coefficients of Resistivity for Various Materials (at 20°C) Material Resistivity(Ω · m) Temperature Coefficientof Resistivity [(°C)−1] Silver 1.59 ✕ 10−8 3.8 ✕ 10−3 Copper 1.7 ✕ 10−8 3.9 ✕ 10−3 Gold 2.44 ✕ 10−8 3.4 ✕ 10−3 Aluminum 2.82 ✕ 10−8 3.9 ✕ 10−3 Tungsten 5.6 ✕ 10−8 4.5 ✕ 10−3 Iron 10.0 ✕ 10−8 5.0 ✕ 10−3 Platinum 11 ✕ 10−8 3.92 ✕ 10−3 Lead 22 ✕ 10−8 3.9 ✕ 10−3 Nichromea 150 ✕ 10−8 0.4 ✕ 10−3 Carbon 3.5 ✕ 10−5 −0.5 ✕ 10−3 Germanium 0.46 −48 ✕ 10−3 Silicon 640 −75 ✕ 10−3 Glass 1010–1014   Hard rubber ≈1013   Sulfur 1015   Quartz (fused) 75 ✕ 1016   (b) If the wire is heated to 32.0°C while the 7.0-V potential difference is maintained, what is the resulting current in the wire?

- A 100 W lightbulb has a resistance of about 12 when cold (20 deg * C) and 156 when on (hot). Estimate the temperature of the filament when hot assuming an average temperature coefficient of resistivity a = 0.0045(C) ^ - 1.