A transistor is used as an amplifier in `CB` mode with a load resistance of `5 k Omega` the current gain of amplifier is `0.98` and the input resistance is `70 Omega`, the voltage gain and power gain respectively are

Options

A. `70, 68.6`
B. `80, 75.6`
C. `60, 66.6`
D. `90, 96.6`

Answer

A

Explanation

CB-
`alpha=0.98`
(Voltage gain) `A_(V)=alpha(R)/(R_("in"))0.98xx(5xx10^(3))/(70)=70`
( Power gain ) `A_(P)` = Current gain `xx` voltage gain
= `0.98 xx70=68.6`