Question
The current in a triode at anode potential $100\,V$ and grid potential $-1.2 \,V is 7.5 \,mA$. If grid potential is changed to $ -2.2\, V$, the current becomes $5.5\, mA$. the value of trans conductance (gm) will be....$mili\, mho$
✓
Answer
(a)${g_m} = {\left( {\frac{{\Delta {I_p}}}{{\Delta {V_g}}}} \right)_{{V_p} = {\rm{constant}}}} = \frac{{(7.5 - 5.5)}}{{ - 1.2 - ( - 2.2)}} = 2m\,mho$
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