I have a question about this circuit. How do i rearrange the formula to calculate the voltage gain of this opamp with a transistor:
I know the formula for the gain of a non-inverting opamp like in the next picture :
and it is, Av = 1 + (R1/R2) (the gain).
But in the first circuit the resistor connected to ground is not there anymore, it is switched to the other side of R2.
So is the formula for gain now, Av = 1+(R2/0), so that the gain is 1 ?
and does the opamp in the first example now act as a voltage follower, so that the voltage is the same on Vout of the opamp ? So that the base of the transistor gets a current of : I = (5V/R1).
Like this circuit :