GATE EC 2020 Set 1 Q18 — Op-amp Circuits

The ideal $\text{OP-AMP}$ circuit shown in the Figure produces output voltage $V_{o}=x$ when the Switch, $\text{S}$, is open. Which of the options represents the output voltage when $\text{S}$ is closed?

A circuit using an ideal $\text{OP-AMP}$ is shown in the Figure. Which of the following options gives the correct value of the current $I_{X}$?

Consider an ideal OP-AMP circuit as shown in the Figure. The resistances $R_{1}=R_{2}=R_{3}=R_{4}=50 \mathrm{~k} \Omega$. The magnitude of the closed loop gain is $\_\_\_\_$ . (rounded off to two decimal places)

Which of the following statements is/are TRUE with respect to an ideal opamp?

​​​​​The opamps in the circuit shown are ideal, but have saturation voltages of $\pm 10 \mathrm{~V}$. Assume that the initial inductor current is $0 \mathrm{~A}$. The input voltage $\left(\mathrm{V}_{\mathrm{i}}\right)$ is a triangular signal with peak voltages of $\pm 2 \mathrm{~V}$ and time period of $8 \mu \mathrm{s}$. Which one of the following …

In the circuit below, the opamp is ideal. If the circuit is to show sustained oscillations, the respective values of $R_{1}$ and the corresponding frequency of oscillation are