$V_{CE}$ and $I_C$
$V_{CB} = V_{CE} - 0.7 volt$ = $ V_{CE} - V_{BE} $
If $V_{CE}$ = 0, $V_{CB}$ = 0.7 volt forward biased
At some instant, $V_{BE}$
At a later instant, $V_{BE}$
$V_{CE} = V_{CC} - I_C R_L$
$V_0 = V_{CC} - I_C R_L$
$\Delta V_0 = -(\Delta I_C) R_L$
$V_{BE} = V_{BB} - I_B R_B + V_S$
$\Delta V_{BE} = -\Delta I_B R_B + \Delta V_S$
If you neglact $\Delta V_{BE}$
$\Delta V_S = (\Delta I_B) R_B$
Voltage gain = $\frac{\Delta V_0}{\Delta V_S}$ = - $\frac{(\Delta I_C) R_C}{(\Delta I_B)R_B}$ = $-B_{ac} \frac{R_L}{R_B}$
$B \simeq$ 50 to few hundred
Voltage gain = $\frac{\Delta V_0}{\Delta V_S}$ = - $\frac{(\Delta I_C) R_C}{(\Delta I_B)R_B} $ = $-B_{ac} \frac{R_L}{R_B}$
$B \simeq$ 50 to few hundred
$V_i = small, I_B = 0 \Rightarrow I_C \simeq 0$
$V_0 = V_{CC} - I_C R_L$
$V_0 = V_{CC}$
if $V_i$ is quite large
$V_0 \simeq 0$