3. This circuit in Figure 9.1 illustrates one of the most common applications of an Op- amp, a closed-loop gain-inverting amplifier. Note that DC signal is applied to the negative (-) input terminal: RI V2 2. F 15V Rf ww 10000 ww 10k Op Amp 1V Vin V1 H 741 Vout 15V RI XMM1 www Figure 9.1 3.1 Using Multisim construct the circuit in Figure 9.1 and study its working principle and performance. a) Analyse the circuit with special attention to the voltages developed across the input resistor (Ri) and the feedback resistor (Rf). Is the voltage across Rf equal to the input voltage Vin? If yes, explain why. Discuss the polarity of the output voltage. Is it negative when the Vin is positive? Is that the reason why this amplifier is called an inverting amplifier? Support your explanation with the appropriate equations for the output voltage and the closed-loop gain. b) After extracting the formulas in part 1 and component values as in the circuit calculate Vout and gain 'm' compare the results with the appropriate readings and verify that the gain 'm' is the ratio of the output voltage to the input voltage. Record it in your logbook. Also, calculate the value of load current using formula: lin Vin/Ri. What is the op-amp total output current? c) Set the various values of Rr and Ri. Note how changes affect the output voltage and gain. Is the gain determined by the external resistors Rf and Ri? Also, try to verify what parameters affect the load current. Is it R₁ and Vout? 3. Discussion on Results and Observations: Summarise the whole lab session in your own words. Discuss what experience you gained after completing this lab exercise. Give a brief account of all the problems you have faced and how did you solve these problems? Also, explain how your last week experience helped you in carrying out this task independently. How does the results correlate with the theory you learned in classes? Give names of some real- world applications where these circuits have been used.