Assignment:
(a) The circuit of FIGURE is known as a trans-impedance circuit used for the measurement of very small currents. Derive the relationship between the output voltage V and the input current I; i.e. if V = kI find k in terms of R1, R2 and Rf.
(b) Calculate the current I if Rf =10 mOhm (milli-Ohms), R1 = 90 kOhm, R2=10 kOhm, and V= 0.1 V.