Given the circuit of figure, calculate the output voltage $V_{\text {out }}$ when $R_L=0 \Omega, 500\ \Omega$, and $1000\ \Omega$.

The following measurements were made on a resistive two-port network: Condition 1 – create a short circuit at port 2 and apply 20 V to port 1: Measurements: I1 = 1 A; I2 = -1 A. Condition 2 – create an open circuit at port 1 and apply 80 V to port 2: Measurements: V1 = 400 V; I2 = 3 A. Find the maximum power that this two-port circuit can deliver to a resistive load at port 2 when port 1 is driven by a 4 A dc current source with an internal resistance of 60Ω.

The circuit in Figure contains a current controlled voltage source. What restriction must be placed on the gain. $R$. of this dependent source to guarantee stability?

A $140-\mathrm{mH}$ inductor and a $4.90-\Omega$ resistor are connected with a two way switch to a $6.00$-V battery.
(a) If the switch is thrown to connect the battery to the circuit, how much time elapses before the current reaches $220 \mathrm{~mA}$ ?
(b) What is the current in the inductor $10.0 \mathrm{~s}$ after the switch is closed?
(c) Now the switch is quickly thrown to disconnect the battery from the circuit and form a series $RL$ circuit. How much time elapses before the current falls to $160 \mathrm{~mA}$ ?

a. Simplify the circuit of the given figure, and write the nodal equations. b. Solve for the node voltages. c. Determine the voltage across the $15-\Omega$ capacitor.

For the circuit of figure, if the resistor is replaced with one with red, red, black color bands, at what voltage do you expect the fuse to blow?

Figure shows a circuit that performs a lowpass STC function. Such a circuit is known as a first-order, low-pass active filter. Derive the transfer function and show that the dc gain is $\left(-R_2 / R_1\right)$ and the 3-dB frequency $\omega_0=1 / C R_2$. Design the circuit to obtain an input resistance of $10 \mathrm{k} \Omega$, a dc gain of $20 \mathrm{~dB}$, and a 3-dB frequency of $10 \mathrm{kHz}$ At what frequency does the magnitude of the transfer function reduce to unity?

Consider the CE amplifier with an emitterdegeneration resistance $R_e$, shown in Fig. earlier(a). It is required to represent the output circuit of the amplifier with the equivalent circuit shown in Fig. earlierb). Here $A_{v o}$ is the open-circuit voltage gain $\left[v_o / v_i\right]_{R_t=\infty}$, and $R_o$ is the output resistance Replace the BJT with its hybrid$\pi$ model, set $R_L=\infty$ (i.e., open-circuit the collector), and show that

$$A_{v o}=-g_m r_o \frac{1-R_e / \beta r_o}{1+R_e / r_\pi}$$

Now, use this result to find the overall short-circuit transconductance $G_m$ (see Fig. P7.44c) and show that

$$G_m \simeq \frac{g_m}{1+g_m R_e}$$

State clearly all the approximations you made to arrive at this expression for $G_m$.

For a BJT with $\beta=100$ and $r_o=100 \mathrm{k} \Omega$ biased at $I_C=0.2 \mathrm{~mA}$ and having a resistance $R_e=250 \Omega$ in its emitter, find $R_o, A_{v o}$, and $G_m$. Also calculate the voltage gain $A_v$ obtained with $R_L=10 \mathrm{k} \Omega$.

Charging and discharging a capacitor. An initially uncharged capacitor $C$ charges through a resistor $R$ for many time constants and then discharges through the same resistor Call $Q_{\max }$ the maximum charge on its plates and $I_{\max }$ the maximum current in the circuit.
(a) Sketch clear graphs of the charge on the plates and the current in the circuit as functions of time for the charging process.
(b) During the discharging process, the charge on the capacitor and the current both decrease exponentially from their maximum values. Use this fact to sketch graphs of the current in the circuit and the charge on the capacitor as functions of time.

A comparator with hysteresis (a) has one trigger point, (b) has two trigger points, (c) has a variable trigger point, (d) is like a magnetic circuit.

(a) A Mealy sequential circuit has one input (x) and one output (z). z = 1 if and only if the most recent input combined with the preceding three inputs was not a valid excess-3 encoding of a decimal digit; otherwise, z = 0. Assume the excess-3 digits are received least significant bit first. Derive a state table for the circuit. Assume that in the reset state all previous inputs were 0. (Six states are sufficient.) (b) Repeat for a Moore circuit (i.e., z = 1 if and only if the previous four inputs were not a valid excess-3 digit). (Eight states are sufficient.) (c) Is it possible for a Moore circuit to generate the correct output while the fourth input bit is present rather than after it has been received? Explain your answer.

The current-versus-voltage plot for a solar panel is shown in the figure. (a) The short-circuit current, $I_{\mathrm{sc}}$ of a solar panel is the current it can generate when a wire connects its output terminals, making the load resistance $R=0$. What is $I_{\mathrm{sc}}$ for this panel? (b) The open-circuit potential, $V_{\mathrm{oc}}$, of a solar panel is the voltage it can generate when it is disconnected from any circuit (infinite load resistance $R$ ). What is $V_{o c}$ for this panel? (c) Calculate the power output of the solar panel at points $A, B, C, D,$ and $E$ in the figure .

In the trigger circuit if $R_1$ is decreased to $50 \mathrm{k} \Omega$, the upper trigger-point voltage will (a) increase (b) decrease (b) not change

When a wire is moved through a magnetic field, does the resistance of the closed circuit affect current only, EMF only, both, or neither?