The term interaction is sometimes used interchangeably with force, and other times interchangeably with potential energy. Although force and potential energy certainly aren't the same thing, what justification is there for using the same term to cover both?

Answer the following question to test your understanding of the preceding section:
What effect does calcitonin have on blood calcium concentration, and how does it produce this effect? Answer the same questions for parathyroid hormone.

A compressor in a commercial refrigerator receives R-410a at −10 F and x = 1. The exit is at 200 psia, 120 F. Neglect kinetic energies and find the specific work.

Answer the following question.

What medical term can be used interchangeably with $aging$?

$$\rule{10cm}{0.15mm}$$

A large slab of concrete, 5$\times$8$\times$0.3 m, is used as a thermal storage mass in a solar-heated house. If the slab cools overnight from 23$^{\circ} \mathrm{C}$ to 18$^{\circ} \mathrm{C}$ in an 18$^{\circ} \mathrm{C}$ house, what is the net entropy change associated with this process?

The electron is known to have a radius no larger than $10^{-18} m.$ If actually produced by circulating mass, its intrinsic angular momentum of roughly A would imply very high speed, even if all that mass were as far from the axis as possible, (a) Using simply rp (from |r X pj) for the angular momentum of a mass at radius r, obtain a rough value of p and show that it would imply highly relativistic speed, (b) At such speeds, $E = ymc^2$ and $p — ymc^2$ combine to give $E \cong pc$ (just as for the speedy photon). How does this energy compare with the known internal energy of the electron?

You have six shelves, one above the other and all above the floor, and six volumes of an encyclopedia, A, B, C, D, E, and F.(a) List all the ways you can arrange the volumes with five on the floor and one on the sixth/top shelf. One way might be (ABCDE, -, -, -, F).(b) List all the ways you can arrange them with four on the floor and two on the third shelf.(c) Show that there are many more ways, relative to' parts (a) and (b), to arrange the six volumes with two on the floor and two each on the first and second shelves. (There are several ways to answer this, but even listing them all won't take forever it's fewer than 100.)(d) Suddenly, a fantastic change! All six volumes are volume X—it's impossible to tell them apart. For each of the three distributions described in parts (a), (b), and (c), how many different (distinguishable) ways are there now?(e) If the energy you expend to lift a volume from the floor is proportional to a shelf's height, how do the total energies of distributions (a), (b), and (c) compare?(f) Use these ideas to argue that the relative probabilities of occupying the lowest energy states should be higher for bosons than for classically distinguishable particles.(g) Combine these ideas with a famous principle to argue that the relative probabilities of occupying the lowest states should be lower for fermions than for classically distinguishable particles.

A vacuum pump is used to evacuate a chamber where some specimens are dried at 50$^{\circ} \mathrm{C}$. The pump rate of volume displacement is 0.5 m3/s, with an inlet pressure of 0.1 kPa and a temperature of 50$^{\circ} \mathrm{C}$. How much water vapor has been removed over a 30-min period?

Wayne Mueller, financial analyst at CELL Corporation, is examining the behavior of quarterly utility costs for budgeting purposes. Mueller collects the following data on machine-hours worked and utility costs for the past 8 quarters:

$$\begin{matrix} \text{Quarter} & \text{Machine-Hours} & \text{Utility Costs}\\ \text{1} & \text{120,000} & \text{\$215,000}\\ \text{2} & \text{75,000} & \text{150,000}\\ \text{3} & \text{110,000} & \text{200,000}\\ \text{4} & \text{150,000} & \text{270,000}\\ \text{5} & \text{90,000} & \text{170,000}\\ \text{6} & \text{140,000} & \text{250,000}\\ \text{7} & \text{130,000} & \text{225,000}\\ \text{8} & \text{100,000} & \text{195,000}\\ \end{matrix}$$

1.Estimate the cost function for the quarterly data using the high-low method. 2. Plot and comment on the estimated cost function. 3. Mueller anticipates that CELL will operate machines for 125,000 hours in quarter 9. Calculate the predicted utility costs in quarter 9 using the cost function estimated in requirement 1.

Here we gain some idea of how small an object would have to be before quantum mechanics might rear its head. The density of aluminum, $2.7 \times 10^3 kg/m^3,$ is typical of solids and liquids around us. Suppose we could narrow down the velocity of an aluminum sphere to within an uncertainty of $1 \mu m$ per decade. How small would it have to be for its position uncertainty to be at least as large as $\frac{1}{10}$ % of its radius?

Liquid water is heated, so it becomes superheated vapor. Can specific heat be used to find the heat transfer? Explain.

You are a new junior accountant at In Focus Corporation, maker of lenses for eyeglasses. Your company sells generic-quality lenses for a moderate price. Your boss, the controller, has given you the latest month’s report for the lens trade association. This report includes information related to operations for your firm and three of your competitors within the trade association. The report also includes information related to the industry benchmark for each line item in the report. You do not know which firm is which, except that you know you are Firm A.

$$\begin{matrix} \text{Unit Variable Costs Member Firms for the Month Ended September 30, 2017}\\ \text{ } & \text{Firm A} & \text{ Firm B} & \text{Firm C} & \text{Firm D} & \text{Industry Benchmark}\\ \text{Materials input} & \text{2.15} & \text{2.00} & \text{2.20} & \text{2.60} & \text{2.15 oz of glass}\\ \text{Materials price} & \text{\$ 5.00} & \text{\$ 5.25} & \text{\$ 5.10} & \text{\$ 4.50} & \text{\$ 5.10 per oz.}\\ \text{Labor-hours used} & \text{0.75} & \text{1.00} & \text{0.65} & \text{0.70} & \text{0.70 hours}\\ \text{Wage rate} & \text{\$ 14.50} & \text{\$ 14.00} & \text{\$ 14.25} & \text{\$ 15.25} & \text{\$ 12.50 per DLH}\\ \text{Variable overhead rate} & \text{\$ 9.25} & \text{\$ 14.00} & \text{\$ 7.75} & \text{\$ 11.75} & \text{\$ 12.25 per DLH}\\ \end{matrix}$$

1. Calculate the total variable cost per unit for each firm in the trade association. Compute the percent of total for the material, labor, and variable overhead components. 2. Using the trade association's industry benchmark, calculate direct materials and direct manufacturing labor price and efficiency variances for the four firms. Calculate the percent over standard for each firm and each variance. 3. Write a brief memo to your boss outlining the advantages and disadvantages of belonging to this trade association for benchmarking purposes. Include a few ideas to improve productivity that you want your boss to take to the department heads' meeting.

Write down the expressions for the physical laws that govern each mode of heat transfer, and identify the variables involved in each relation.

“All overhead costs are relevant in NPV analysis.” Do you agree? Explain.