TABLE 22.1 Resistivities of materials Resistivity (N •m) Material Copper 1.7 × 10-8 Aluminum 2.7 × 10-8 -8- Tungsten (20°C) 5.6 X 10–8 Tungsten (1500°C) 5.0 × 10-7 Iron 9.7 × 10–8 Nichrome 1.5 × 10-6 Seawater 0.22 Blood (average) 1.6 Muscle 13 Fat 25 Pure water 2.4 X 105 Cell membrane 3.6 X 107

TABLE 22.1 Resistivities of materials Resistivity (N •m) Material Copper 1.7 × 10-8 Aluminum 2.7 × 10-8 -8- Tungsten (20°C) 5.6 X 10–8 Tungsten (1500°C) 5.0 × 10-7 Iron 9.7 × 10–8 Nichrome 1.5 × 10-6 Seawater 0.22 Blood (average) 1.6 Muscle 13 Fat 25 Pure water 2.4 X 105 Cell membrane 3.6 X 107

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter20: Electric Current, Resistance, And Ohm's Law

Section: Chapter Questions

Problem 9CQ: In which of the three semiconducting materials listed in Table 20.1 do impurities supply free...

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2.1 A piece of wire l cm long carries a current I when a voltage V is applied across its ends at a temperature of 0°C. If the resistivity of the material of which the wire is made varies as shown in the figure, what length of the same diameter wire is needed so that the same current flows when the same voltage is applied at temperature 400°C? 12 10 200 400 600 800 1000 Temperature ("C) Resistivity (10 Qm)
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