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Q.
The input characteristics of a transistor in $CE$ mode is the graph obtained by plotting
KCETKCET 2015Semiconductor Electronics: Materials Devices and Simple Circuits
Solution:
Input characteristics curve is drawn between base current $I_{B}$ and emitter base voltage $V_{R B}$ at constant collector emitter voltage $V_{C B}$ Dynamic input resistance,
$R_{i}=\left(\frac{\Delta V_{B E}}{\Delta I_{B}}\right)_{V_{C E}}=\text { constant }$