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Electric Current through Gases — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysicsElectric Current through Gases4 Marks
Question
Let $\text{i}_0$ be the thermionic current from a metal surface when the absolute temperature of the surface is $\text{T}_0$. 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 $\Big(\frac{\text{i}}{\text{i}_0}\Big)$ against $\Big(\frac{\text{T}}{\text{T}_0}\Big)?$
✓

Answer

  1.  

Explanation:
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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