(a) A 33.9-m length of copper wire at 20.0°C has a radius of 0.27 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 Nichromea Carbon Germanium Silicon Glass Hard rubber Sulfur Resistivity (2. m) 1.59 x 10-8 1.7 x 10-8 2.44 x 10-8 2.82 x 10-8 5.6 x 10-8 10.0 x 10-8 11 x 10-8 22 x 10-8 150 x 10-8 3.5 x 10-5 0.46 640 1010-1014 ≈1013 1015 Quartz (fused) 75 x 1016 Temperature Coefficient of Resistivity [(°C)-¹] 3.8 x 10-3 3.9 x 10-3 3.4 x 10-3 3.9 x 10-3 4.5 x 10-3 5.0 x 10-3 3.92 x 10-3 3.9 x 10-3 0.4 x 10-3 -0.5 x 10-3 -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 current in the wire?

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(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…

A 2.0 mm diameter iron wire ( resistivity, p = 9.7 x 10-° 2-m) carries a current of 2.5 A. Determine the potential difference across this 20m length of the wire. (A 1.544 v B 0.544 v C) 1.618 v 0.618 v

Platinum has a resistivity of 10.6×108 m at 20°C. What will the resistivity of platinum when then temperature is increased to 1000°C. (Take a as 3.927×10-³)

(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?