Q. The slopes of anode and mutual characteristics of a triode are $0.02\ mA\ V^{- 1}$ and $1\ mA\ V^{- 1}$ respectively. What is the amplification factor of the valve
A) 5
B) 50
C) 500
D) 0.5
Explanation
(b) The slope of anode characteristic curve $= \frac{1}{r_{p}}$
$\Rightarrow r_{p} = \frac{1}{0.02\ mA/V} = 50\frac{V}{mA} = 50 \times 10^{3}\frac{V}{A}$
The slope of mutual characteristic curve $= g_{m}$
$= 1 \times 10^{- 3}A/V$
$\therefore\ \mu = r_{p} \times g_{m} = 50 \times 10^{3} \times 10^{- 3} = 50$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.