# voltage gain of npn transistor

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As V$_{in}$ increases V(out) also increases.
Then how can we say Av is negative and its magnitude is increasing'

asked Mar 27, 2017
It is not clear to me what you are asking. Are you saying that "gain" means that the output must be bigger (more +ve) than the input? "Gain" means that the output is *bigger in magnitude*, but it can be the *opposite polarity* to the input.
Topic : Common Base Voltage Gain
http://www.electronics-tutorials.ws/transistor/tran_1.html

How it can be opposite polarity
Ts there no explanation in the given answer?
No , this is the full question.
Voltage gain = $\frac{V_{out}}{V_{in}}$
$V_{out}=V_{cb}$
$V_{in}=V_{eb}$
Electronics is one of my weak points. I think this transistor acts as a throttle. Gain decreases as input voltage is increased, as in 4.