MCQ
Thermionic emission from a heated filament varies with its temperature $T$ as
- A$T^{-1}$
- B$T$
- ✓$T^2$
- D$T^{3 / 2}$
✓
Answer
Correct option: C.
$T^2$
According to Richardson-Dushman equation, number of thermions emitted per sec per unit area $J=A T^2 e^{-W_0 / k T} \Rightarrow$ $J \propto T^2$
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