Calculate the number of molecules in a. one cubic centimeter of liquid water at room

Read the definition of engineering in * 1.1. How does this compare with your ideas of what engineering is? What is sin1ilar? What is different?

Given the definition of engineering in l.l, what do you think that you should be learning? How do you know if you have learned it?

Should the definition of engineering in 1.1 include the idea that engineers also need to be very good with humanities and ~cial sciences? What do you believe? Why?

Select an engineered design (e.g., hydroelectric power as in a dam, an artificial heart) that involves fluid mechanics and is also highly motivating to you. Write a one-page essay that addresses the following questions. Why is this application motivating to you? How docs the system you selected work? What role did engineers play in the design and development of this system?

Many engineering students believe that fixing a washing machine is an example of engineering because it involves llOiving a problem. Write a brief essay in which you address the iollowing questions: Is fixing a washing machine an example of engineering? Why or why not? How do your ideas align or misalign with the definition of engineering given in 1.1?

Propose three new rows for Table l.l,(p.4, 1.2) and fill them in.

Based on molecular mechanisms, explain why aluminum 'Tielts at 660C, whereas ice will melt at oc.

The continuum assumption (select all that apply) a. applies in a vacuum such as in outer space b. assumes that fluids are infinitely divisible into smaller and smaller parts c. is a bad assumption when the length scale of the problem or design is simiJar to the spacing of the molecules d. means that density can idealized as a continuous function of position e. only applies to gases

A fluid parlide a. IS defined as one molecule b. is small given the scale of the problem being considered c. is so small that the continuum assumption does not appl}'

In Table F.2 (front of book), ftnd the hydrostatic equation. For each form of the equation that appears, list the name, S}mbol, and primary dimensions of each variable.

For each of the following units in Table F.l (front of book), present in terms of its primary c.limensions: kWh, poise, slug, cfm, eSt.

ln the context of measurement, a dimension is: a. a category for measurement b. a standard of measurement for size or magnitude c. an increment for measuring "how much"

What is the approximate mass in units of slugs for a. a 2-liter bottle of water? b. a typical adult male? c. a typical automobile?

In the following list, identify which parameters are dimensions and which paramentcrs are unit.~: ~lug, mass. kg, energy/time, meters, horsepower, pressure, and pascals.

Of the three lists below, which sets of units are consbtent? Select all that apply. a. pounds-mass, patmds-force, feet, and seconds. b. slugs, pounds-force, feet, and seconds c. kilograms, newtons, meters, and seconds.

In your own words, describe what actions need to be taken in each step of the grid method.

Which of these is a correct conversion ratio? Select all that apply. a. 1 = l hp/(550 ft-lbf/s) b. 1 ""' l 01.3 kPa/(14.7lbf/in2 ) c. 1 = 3.785 U.S. gal/(1.0 L)

If the local atmospheric pressure is 93 kPa, usc the grid method to find the pressure in units of a. psia b. psf c. bar d. atmospheres e. feet of water f. inches of mercury

The pressure rise !lp associated with wind hitting a window of a building can be estimated using the formula !lp = p( vz/2), where fl is density of air and Vis the speed of the wind. Apply the grid method to calculate pressure rise for p = 1.2 kg/m3 and V = 60 mph. a. Express your answer in pascals. b. Express your answer in pounds-force per square inch (psi). c. E..'{press your answer in inches of water column (in HzO).

Apply the grid method to calculate force using F = rna. a. Find force in newtons form = 10 kg and a = 10 m/s2 . b. GO - Find force in pounds-force form - 10 Ibm and a = 10 ft/s2 c. ;;:u.s Hnd force in newtons form= 10 slug and a = 10 ft/s .

When a bicycle rider is traveling at a speed of V = 24 mph, the power P she needs to supply is given by P = fV, where F = 51bf is the force necessary to overcome aerodynamic drag. Apply the grid method to calculate: a. power in watts. b. energy in food calories to ride for 1 hour.

Apply the grid method to calculate the cost in U.S. doUars to operate a pump for one year. The pump power is 20 hp. The pump operates for 20 hr/day, and electricity costs SO.IO per k\Vh. Ideal Gas law (IGL) ( 1.6)

Start with the ideal gas law and prove that a. Boyle's law is true. b. Charles's law is true.

Calculate the number of molecules in a. one cubic centimeter of liquid water at room conditions b. one cubic centimeter of air at room conditions

Start with the mole-form of the ideal gas law and show the steps to prove that the mass form is corred. 1.28 Start with the universal gas constant and show that R,.,-2 = 297 J /(kg K).

A spherical tank hold~ C01 at a pressure of3 atm<>spheres and a temperature of 20C. During a fire. the temperature is increased by a factor of 4 to 80C. Does the pressure also increase by a factor of 4? Justify your answer using equations.

An engineer living at an elevation of 2500 ft is conducting experiments to verify predictions of glider performance. To process data, density of ambient air is needed. The engineer measures temperature (74.3F) and atmospheric pressure (27.3 inches of mercury). Calculate density in units of kg/m). Compare the calculated value with data from Table A.2 and make a recommendation about the effects of elevation on density; that is, are the effects of elevation significant?

Determine the density of methane gas at a pressure of 300 kN!m2 absolute and 60C.

A spherical tank is being designed to hold 10 mole5 of methane gas at a pressure of 2 bar and a temperature of 70F. What diameter spherical tank should be used?

Natural gas is stored in a spherical tank at a temperature of l 0C. At a given iniltal time, the pressure in the tank is I 00 kPa gage, and the atmospheric pressure is 100 kPa absolute. Some time later. after considerably more gas is pumped into the tank, the pressure in the tank is 200 kPa gage, and the temperature is still10C. What will be the ratio of the mass of natural gas in the tank when p = 200 kPa gage to that when the pressure was 100 kPa gage?

At a temperature of 100C and an absolute pressure of 5 atmospheres, what is the ratio of the density of water to the density of air, p,./p.?

find the total weight of a 6ft~ tank of oxygen if the oxygen is pressurized to 400 psia, the tank itself weighs 90 lbf, and the temperature is 70F.

A 4m3 oxygen tank is at 20"C and 700 kPa. The valve is opened, and some oxygen is released until the pres~ure in the tank dropl> to 500 kPa. Calculate the mass of oxygen that has been released from the tank if the temperature in the tank does not change during the process.

What is the (a) ~pecilic weight, and (b) density of air at an absolute pressure of 600 kPa and a temperature of soc?

Meteorologists often refer to air masses in forecasting the weather. Estimate the mass of I rni\ of air in slugs and kilogran1s. Make your own reasonable assumptions with respect to the conditions of the atmosphere.

A bicycle rider has several reasons to be interested in the effects of temperature on air density. The aerodynantic drag force decreases linearly with density. Also. a change in temperature will affect the tire pressure. a. To visualize the effects of temperature on air densit)~ write a computer program that calculates the air density at atmospheric pressure for temperatures from - l0C to soc. b. Also assume that a bicycle Lire was inflated to an absolute pressure of 450 kPa at 20C. Assume the volume of the tire does not change with temperature. Write a program to show how the tire pressure changes with temperature in the same temperature range, - l0C to 50C.

A team is designing a helium-filled balloon that will fly to an altitude of 80,000 ft. As the balloon ascends, the upward force (buoyant torce) will need to exceed the total weight. TI1us, weight is critical. Estimate the weight (in newtons) of the helium inside the balloon. The balloon is inflated at a site where the atmospheric pressure is 0.89 bar and the temperature is 22C. When inflated prior to launch, the balloon is spherical (radius 1.3 m) and the inflation pressure equals the local atmospheric pressure.

Apply the WWM and the grid method to find the acceleration for a force of 2 N acting on an object of mass 7 ounces. The relevant equation is Newton's second law of motion, F = ma. Work in SI units, and provide the answer in meters per second squared {m/s2 ).

In Example 1.2 (p. 16, 1.7), what are the three steps that an engineer takes to "State the GoaJ?

for Problem 1.37 above, complete the "Define the Situation;' "State the Goat: and "Generate Ideas and Make a Plan" operations of the WWM.

The hydrostatic equation is pl-y + z = C, where p is pressure, 'Y is specific weight, z is elevation, and Cis a conbtant. Prove that the hydrostatic equation i~ dimensionally homogeneous.

find the primary dimensions of each of the following terms. a. (p V2 )/2 (kinetic pressure). where pis fluid den sit)' and Vis velocity b. T (torque) c. P (power) d. {p V2 L)/u (Weber number), when: p is fluid density, Vis velocity, L is length, and u is surface tension

The power provided by a centrifugal pump is given by p = lngh, where m is mass flow ratc,g is the gravitational constant, and h is pump head. Prove that this equation i~ dimensionally homogeneous

Find the primary dimensions of each of the following terms. a. J p V2 dA, where pis fluid density, Vis velocity, and A is area. A df d b. dl ,/ V dV:, where dt is the derivative with respect to time, p is density, and is volume.