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Question
Let i0 be the thermionic current from a metal surface when the absolute temperature of the surface is T0. The temperature is slowly increased and the thermionic current is measured as a function of temperature. Which of the following plots may represent the variation in (i/i0) against (T/T0)?
Options
a
b
c
d
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Solution
d
Since the thermionic current is directly proportional to the square of the temperature of the surface emitting thermions, the graph is parabolic.
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