A tantalum rod of diameter 3 mm and length 120 mm is supported by two electrodes within a large vacuum enclosure. Initially the rod is in equilibrium with the electrodes and its surroundings, which arc maintained at 300 K. Suddenly, an electrical current,
(a) Estimate the time required for the midlength of the rod to reach 1000K.
(b) Determine the steady-state temperature distribution and estimate approximately how long it will take to reach this condition.
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Introduction to Heat Transfer
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