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Question
The dynamic plate resistance of a triode value is 10 kΩ. Find the change in the plate current if the plate voltage is changed from 200 V to 220 V.
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Solution
Given:-
Plate resistance,
`r_p=10kOmega=10^4Omega`
Change in plate voltage,
`deltaV_p=220-200=20V`
Plate resistance at constant grid voltage is given as:-
\[r_P = \left(\frac{\delta V_P}{\delta I_P}\right)_{V_G = Constant} \]
\[ \Rightarrow \delta I_P = \frac{\delta V_P}{r_P}\]
\[\delta I_P = \frac{\delta V_p}{r_P}\]
\[\delta I_P = \frac{20}{{10}^4} = 0 . 002 A = 2\text{ mA}\]
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