Electronic Devices Question 266
Question: The slopes of anode and mutual characteristics of a triode are 0.02 $mAV^{-1}$ and 1 $mAV^{-1}$ respectively. What is the amplification factor of the valve
[MP PMT 1990]
Options:
A) 5
B) 50
C) 500
D) 0.5
Show Answer
Answer:
Correct Answer: B
Solution:
The slope of anode characteristic curve $ =\frac{1}{r _{p}} $
$ \Rightarrow r _{p}=\frac{1}{0.02mA/V}=50\frac{V}{mA}=50\times 10^{3}\frac{V}{A} $
The slope of mutual characteristic curve = gm = 1 x 10${^3}$ A/V.
$ \therefore \mu =r _{p}\times g _{m}=50\times 10^{3}\times {{10}^{-3}}=50 $ .
