A Tungsten w ire is 1.50 m long and has a diameter of 1.00 mm. At 20.°C a current of 50. mA flows through the wire. [?=5.6 × 10-8 ? ? m; ?=0.0045(C°)-1]
(a) Determine the potential across the wire.
(b) If the wire temperature increases by 100. C°, what potential is now required to produce a current of 50. mA?
(a) 5.4 mV
(b) 7.8 mV
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