Is the power generated by fuel cells limited by the Carnot efficiency? Explain.

Suppose a utility generates electricity with a 36 percent efficient coal-fired power plant emitting the legal limit of of $\mathrm{SO}_{2}$ per million Btus of heat into the plant. Suppose the utility encourages its customers to replace their incandescents with compact fluorescent lamps (CFLs) that produce the same amount of light. Over the 10,000-hr lifetime of a single CFL, (a) How many kilowatt-hours of electricity would be saved? (b) How many tons of $\mathrm{SO}_{2}$ would not be emitted? (c) If the utility can sell its rights to emit $\mathrm{SO}_{2}$ at $800 per ton (these are called “allowances”; see Chapter 7), how much money could the utility earn by selling the$$\mathrm{SO}$_{2}$ saved by a single CFL?

A rigid 1-ft^3 vessel contains R-134a originally at -20$^\circ{}$F and 27.7 percent quality. The refrigerant is then heated until its temperature is 100$^\circ{}$F. Calculate the heat transfer required to do this. Answer: 84.7 Btu

The differential amplifier in Figure P11.64 has a pair of PMOS transistors as input devices and a pair of NMOS transistors connected as an active load. The circuit is biased with $I_Q=0.2 \mathrm{~mA}$, and the transistor parameters are: $K_n=K_p=0.1 \mathrm{~mA} / \mathrm{V}^2, \quad \lambda_n=0.01 \mathrm{~V}^{-1}, \quad \lambda_p=0.015 \mathrm{~V}^{-1}$, $V_{T N}=1 \mathrm{~V}$, and $V_{T P}=-1 \mathrm{~V}$. (a) Determine the quiescent drain-to source voltage in each transistor. (b) Find the open-circuit differential mode voltage gain. (c) What is the output resistance?

(a) Make sure that you can follow all of the examples, especially the propagation of borrows in the subtraction process. (b) To make sure that you understand the borrowing process, work out a detailed analysis in terms of powers of 2 for the following example:

$$\begin{array}{r} 1100 \\ -101 \\ \hline 111 \end{array}$$

An insulated cylinder fitted with a fractionless piston contains saturated vapor R-12 at ambient temperature, $20^{\circ} \mathrm{C}$. The initial volume is 10 L. The R-12 is now expanded to a temperature of $-30^{\circ} \mathrm{C}$. The insulation is then removed from the cylinder, allowing it to warm at constant pressure to ambient temperature. Calculate the net work and the net entropy change for the overall process.

If the pump in the given figure is installed in the system of the mentioned problem, what will be the rate of discharge of water from the lower tank to the upper one?

An Ericsson cycle operates between thermal energy reservoirs at $627^{\circ} \mathrm{C}$ and $7^{\circ} \mathrm{C}$ while producing $500 \mathrm{~kW}$ of power. Find the rate of heat addition to this cycle when it is repeated $2000$ times per minute.

Expand the function in a Laurent series that converges for 0<|z|<R and determine the precise region of convergence. Show the details of your work. sin πz/z²

Repeating the instructions of determining the frequency response $V_{\text {out }}(j \omega) / V_{\text {in }}(j \omega)$ for the circuit of the figure. Assume $L=0.5 \mathrm{H}$ and $R=200 \mathrm{k} \Omega$. b. Plot the magnitude and phase of the circuit for frequencies between $10$ and $10^{7} \mathrm{rad} / \mathrm{s}$ on graph paper, with a linear scale for frequency. c. Repeating the plot the magnitude and phase of the circuit for frequencies between $10$ and $10^{7} \mathrm{rad} / \mathrm{s}$ on graph paper, with a linear scale for frequency., using semilog paper. (Place the frequency on the logarithmic axis.)Plot the magnitude response on semilog paper with magnitude in decibels. for the circuit of the figure.

A 60-kg ice skater is standing on ice with ice skates (negligible friction). She is holding a flexible hose (essentially weightless) that directs a 2-cm-diameter stream of water horizontally parallel to her skates. The water velocity at the hose outlet is 10 m/s relative to the skater. If she is initially standing still, determine (a) the velocity of the skater and the distance she travels in 5 s and (b) how long it will take to move 5 m and the velocity at that moment.

What is the minimum value of $\beta_{\mathrm{DC}}$ that makes $R_{\mathrm{IN}(\mathrm{BASE})} \geqq 10 K_2$ ?

Is the efficiency of a thermoelectric generator limited by the Carnot efficiency? Why?

The brake horsepower and water horsepower of a pump are determined to be 15 kW and 12 kW, respectively. If the flow rate of water to the pump under these conditions is $0.05 m^3/s$, the total head loss of the pump is (a) 11.5 m(b) 9.3 m(c) 7.7 m(d) 6.1 m(e) 4.9 m