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Hot water is flowing at an average velocity of 1.5 m/s through a cast iron pipe (k 5 52 W/mK) whose inner and outer diameters are 3 cm and 3.5 cm, respectively. The pipe passes through a 15-m-long... A computer IC chip consumes 10 W of power, which is dissipated as heat. The chip measures 4 cm by 4 cm on a side and is 0.5-cm thick. Currently the IC chip is packaged into an electronic device as... An apparatus, used in an operating room to cool blood, consists of a coiled tube that is immersed in an ice bath. Using this apparatus, blood, flowing at 0.006 m 3 /h, is to be cooled from 40C to... A gas stream of flow rate 10.0 lbmole/ft 2 · h contains 6.0% sulfur dioxide (SO 2 ) by volume in air. It is desired to reduce the SO 2 level in the treated gas to no greater than 0.5% in a... An electric resistance space heater is designed such that it resembles a rectangular box 50 cm high, 80 cm long, and 15 cm wide filled with 45 kg of oil. The heater is to be placed against a wall,... The set-point of the control system under proportional control (K c = 5) undergoes a step change of magnitude 2. For (a) Determine when the maximum value of y occurs. (b) Determine the offset. (c)... The following transfer function is not written in a standard form: (a) Put it in standard gain/time constant form. (b) Determine the gain, poles and zeros. (c) If the time-delay term is replaced by a... A long cylinder with radius b and volume charge density has a spherical hole with radius a < b centered on the axis of the cylinder. What is the electric field strength inside the hole at radial... The variation of the spectral absorptivity of a surface is as given in Fig. P2144. Determine the average absorptivity and reflectivity of the surface for radiation that originates from a source at T... Calculate the total lift force on the Arctic hut shown below as a function of the location of the opening. The lift force results from the difference between the inside pressure and the outside... A chemist identifies compounds by identifying bright lines in their spectra. She does so by heating the compounds until they glow, sending the light through a diffraction grating, and measuring the... A wire is made by welding together two metals having different densities. FIGURE P16.59 shows a 2.00-m-long section of wire centered on the junction, but the wire extends much farther in both... The London bobby whistle has a frequency of 2500 Hz. If such a whistle is given a 3.0 s blast, (a) What is the uncertainty in the frequency? (b) How long is the wave train of this blast? (c) What... A problem of practical interest is to make a beam of electrons turn a 90? corner. This can be done with the parallel-plate capacitor shown in FIGURE P23.54. An electron with kinetic energy 3.0 10... Derive the stiffness matrix for a beam element with a nodal linkagethat is, the shear is 0 at node i, but the usual shear and moment resistance are present at node j (see following figure). m; m, L.... A typical pack of freshly fallen snow has a density of 100 kg m -3 and consists of ice crystals which can be modelled as spheres of radius 0.5 mm. Show that if the snow pack is sufficiently deep it... Use the data from Figure 40.24 to calculate the first three vibrational energy levels of a C = O carbon-oxygen double bond. Transmission (%) 100- 75- 1-2 transition of a C-CH, bond 50- 1-2 transition... When two horizontal forces are exerted on the car in Problem 39, 220 N forward and 180 N backward, the car undergoes acceleration. What additional force is needed to produce non-accelerated motion? A spherical gel capsule of 0.50 cm diameter is used a drug delivery device. Initially, there is a total drug amount 0.005 mmole uniformly loaded into the gel material. The capsule is ingested, and... Three positive charges are located along a line, as in the diagram. The 0.10-C charge at point A is 2 m to the left of the 0.02-C charge at point B, and the 0.04-C charge at point C is 1 m to the... Show that the liquid-level system consisting of two interacting tanks (Fig. 6.11) exhibits over damped dynamics; that is, show that the damping coefficient in Eq. 6-57 is larger than one. di h2 hi R2... A 60-kg woman in an elevator is accelerating upward at a rate of 1.2 m/s 2 . a. What is the net force acting upon the woman? b. What is the gravitational force acting upon the woman? c. What is the... Sunlight passing through a pinhole in a piece of paper casts an image of the Sun, as shown. The image size depends on the distance from the pinhole to the floor. If the paper with the pinhole is held... Consider an idealized flat-plate solar collector. Assume that there are no heat losses to conduction or convection. Assume that the insolation is 1000 W/m 2 incident at an angle of 45 from the... Fig. E7.12 presents the response of a system to a unit step in the input. (a) Use these data to derive an FOPTD model of this system. (b) Plot the response of the model and compare with the data. (c)... Consider the novel nanostructured catalyst surface shown in the figure below. The catalyst support consists of an ordered array of cylindrical nanowells of 50 nm diameter and 200 nm depth (1 nm = 10... One step of the manufacturing of silicon solar cells is the molecular diffusion (doping) of elemental phosphorous (P) into crystalline silicon to make an n-type semiconductor. This Pdoped layer needs... A nuclear power plant operates at a maximum temperature of 375 C and produces 1GW of electric power. If the waste heat is dumped into river water at a temperature of 20 C and environmental... Consider the micro scale apparatus shown in the figure on the next page. This apparatus is designed to deliver a small, steady stream of methanol (MeOH) vapor to a separate device that reforms the... A heat engine uses a diatomic gas that follows the pV cycle in FIGURE P21.59. a. Determine the pressure, volume, and temperature at point 2.b. Determine E th , W s , and Q for each of the three... Charge Q is uniformly distributed along a thin, flexible rod of length L. The rod is then bent into the semicircle shown in FIGURE P23.47. a. Find an expression for the electric field E at the center... Consider the two feedback control strategies shown in Fig. 12.6 (with G = G v G p G m ) and the following transfer functions: (a) Design an IMC controller,G c , using a filter, f = 1/(Ï c s +... What is the fundamental frequency of the steel wire in FIGURE P17.48? 75 g steel wire 4.0 kg bar 45 2.0 m 8.0 kg FIGURE P17.48 A process waste gas stream containing 5.0 mole% of benzene (solute A) enters the bottom of a packed tower. The tower is packed with 0.5-inch ceramic Raschig rings, and the diameter of the tower is... A keratometer is an optical device used to measure the radius of curvature of the eyes corneaits entrance surface. This measurement is especially important when fitting contact lenses, which must... A 12-cm-long thin rod has the nonuniform charge density (x) = (2.0 nC/cm)e -|x|/(6.0 cm) , where x is measured from the center of the rod. What is the total charge on the rod? Sirius B has a mass and radius of 2.1 x 10 30 kg and 5.5 x 10 6 m, respectively. Assuming Sirius B is perfectly spherical in shape, compute the ratio of the t f t / t d . Using this result, confirm... A liquid-phase reversible reaction, A B, takes place isothermally in the continuous stirred-tank reactor shown in Fig. E15.8. The inlet stream does not contain any B. An over-ï¬ow line... A rocket fires a projectile at a speed of 0.95c while traveling past the earth. An earthbound scientist measures the projectiles speed to be 0.90c. What was the rockets speed as a fraction of c? (a) Find E in the plane z = 0 that is produced by a uniform line charge, L , extending along the z axis over the range L < z < L in a cylindrical coordinate system. (b) If the finite line charge is... Consider the FOPTD model in Eq. 12-10 with K = 5, = 4, and = 3. Design PI and PID controllers using the IMC tuning method with c = = 3. Simulate the closed loop systems for a unit step change in... For the reliability analysis of the flow control loop in Example 10.4, the DP flow meter is the least reliable component. Suppose that a second, identical flow meter is used in a backup mode so that... Two disks are oriented on parallel planes separated by a distance of 10 in., as shown in the accompanying figure. The disk to the right is 4 in. in diameter and is at a temperature of 500°F. The... FIGURE Q21.4 shows the pV diagram of a heat engine. During which stage or stages is (a) Heat added to the gas, (b) Heat removed from the gas, (c) Work done on the gas, (d) Work done by the gas? P2-... The 10 mg bead in FIGURE P8.48 is free to slide on a frictionless wire loop. The loop rotates about a vertical axis with angular velocity Ï. If v is less than some critical value Ï c , the... A 3200 kg helicopter is flying horizontally. A 250 kg crate is suspended from the helicopter by a massless cable that is constantly 20 from vertical. What propulsion force F prop is being provided by... The graph in Figure 1.38 shows the distance versus time for an elevator as it moves up and down in a building. Compute the elevators velocity at the times marked a, b, and c. 32 28 24 20 16 12 a 28... At 10 GHz and a certain incidence angle, the apparent brightness temperatures of sea water, first-year ice and multi-year ice are 80 K, 252 K and 200 K respectively. At 37 GHz these figures become... A falling liquid film within a gasliquid contactor of 1.50 m length is in contact with 100% carbon dioxide gas at 1.0 atm and 25C. The wetted surface area is 0.50 m 2 , and the liquid film thickness... A 1000 kg cart is rolling to the right at 5.0 m/s. A 70 kg man is standing on the right end of the cart. What is the speed of the cart if the man suddenly starts running to the left with a speed of... A counter-flow double-pipe heat exchanger with A s = 9.0 m 2 is used for cooling a liquid stream (c p = 3.15 kJ/kgK) at a rate of 10.0 kg/s with an inlet temperature of 90C. The coolant (c p = 4.2... A toy gyroscope has a ring of mass M and radius R attached to the axle by lightweight spokes. The end of the axle is distance R from the center of the ring. The gyroscope is spun at angular velocity... Consider a cylinder with a length of 15 cm and a diameter of 10 cm. The cylinder has a surface temperature of 43C, while the room air temperature is 17C. Determine whether placing the cylinder... For the two input two output process in Example 18.2, use Simulink to check the stability regions in Fig. 18.6 for the 1-1, 2-2 controller pairing. Set K c1 = 1, and try three values of K c2 (-1, 0,... How much energy is consumed by (a) A 1.2 kW hair dryer used for 10 min. (b) A 10 W night light left on for 24 h? A 3,000-kg truck runs into the rear of a 1,000-kg car that was stationary. The truck and car are locked together after the collision and move with speed 9 m/s. What was the speed of the truck before... 0.020 mol of gas undergoes the process shown in FIGURE EX18.37. a. What type of process is this? b. What is the final temperature in °C? c. What is the final volume V 2 ? p (atm) 3- 2- 1- V (cm)... Since only changes in potential energy are important in any problem, a student decides to let the elastic potential energy of a spring be zero when the spring is stretched a distance x 1 . The... Consider current I passing through a resistor of radius r, length L, and resistance R. a. Determine the electric and magnetic fields at the surface of the resistor. Assume that the electric field is... It is desired to recover hexane vapor (solute A) from air using an absorption process. The absorption solvent is a nonvolatile mineral oil, which has a mass density of 0.80 g/cm 3 and a molecular... If the bodys center of mass were not placed on the rotational axis of the turntable, how would the persons measured moment of inertia compare to the moment of inertia for rotation about the center of... The solar system is 25,000 light years from the center of our Milky Way galaxy. One light year is the distance light travels in one year at a speed of 3.0 10 8 m/s. Astronomers have determined that... Charges -q and +2q in FIGURE P23.39 are located at x = ±a. Determine the electric field at points 1 to 4. Write each field in component form. y 2a +1 2 3 -2a +29 2a -a- -2a +4 FIGURE P23.39 A gyroscope is precessing as in Fig. 10.32. What happens if you gently add some weight to the end of the flywheel axis farthest from the pivot? Circular motion of flywheel axis (precession) Flywheel... A friend says that the reason why you feel uncomfortable in muggy weather is that water molecules in the air are giving up energy while bombarding you. Do you agree or disagree with your friend? The closed cylinder of FIGURE CP18.74 has a tight-fitting but frictionless piston of mass M. The piston is in equilibrium when the left chamber has pressure p 0 and length L 0 while the spring on the... A +2.0 nC charge is at the origin and a -4.0 nC charge is at x = 1.0 cm. a. At what x-coordinate could you place a proton so that it would experience no net force? b. Would the net force be zero for... A column of water in a vertical pipe has a cross-sectional area of 0.2 m 2 and a weight of 450 N. What is the increase in pressure (in Pa) from the top to the bottom of the pipe? A BiCMOS amplifier is shown in Fig. 3.78. Calculate the small-signal voltage gain v o / v i . Assume I S = 10 16 A, β F = 100, r b = 0, V A , μ n C ox = 200 µA / V 2 ,... A spherical silica gel adsorbent particle of 0.20 cm diameter in placed in a rapidly flowing air stream at a velocity of 50 cm/s containing 1.0 mole% of H 2 O vapor at total system pressure of 1.0... A double-pipe, countercurrent heat exchanger is used to cool a hot liquid stream of biodiesel from 60C to 35C. Biodiesel flows on the shell side with a volumetric flow rate of 3 m 3 /h; water is used... Put in order, from beginning to end, the steps in stream formation: (a) Runoff forms, (b) Rain drops strike the ground, (c) The stream channel forms, (d) Gullies form. What is the de Broglie wavelength of a neutron that has fallen 1.0 m in a vacuum chamber, starting from rest? A sled and rider with a total mass of 40 kg are perched at the top of a hill as pictured in the diagram. The top of this hill is 40 m above the low point in the path of the sled. A second hump in the... Consider a process model: For a step input, show that: (a) y(t) can exhibit an extremum (maximum or minimum value) in the step response only if (b) Overshoot occurs only for Ï a /Ï 1 > 1.... A uniform bar has mass 0.0120 kg and is 30.0 cm long. It pivots without friction about an axis perpendicular to the bar at point a (Fig. P27.72). The gravitational force on the bar acts in the... A block on a frictionless table is connected as shown in FIGURE P15.75 to two springs having spring constants k 1 and k 2 . Find an expression for the blocks oscillation frequency f in terms of the... A less-dense liquid of density 1 floats on top of a more-dense liquid of density 2 . A uniform cylinder of length l and density , with 1 < < 2 , floats at the interface with its long axis... A 280 Hz sound wave is directed into one end of the trombone slide seen in FIGURE CP17.77. A microphone is placed at the other end to record the intensity of sound waves that are transmitted through... A uniform marble rolls without slipping down the path shown in Fig. P10.80, starting from rest. (a) Find the minimum height h required for the marble not to fall into the pit. (b) The moment of... An incandescent lightbulb is an inexpensive but highly inefficient device that converts electrical energy into light. It converts about 10 percent of the electrical energy it consumes into light... A rocket with mass 5.00 10 3 kg is in a circular orbit of radius 7.20 10 6 m around the earth. The rockets engines fire for a period of time to increase that radius to 8.80 10 6 m, with the orbit... It is desired to reduce the concentration of CO 2 in the ï¬ue gas from a coal-fred power plant, in order to reduce greenhouse gas emissions. The efï¬uent ï¬ue gas is sent... It is common practice to treat wooden telephone poles with tar-like materials to prevent damage by water and insects. These tars are cured into the wood at elevated temperatures and pressures.... A pond containing a suspension of microorganisms is used to biologically degrade dissolved organic materials in wastewater, as shown in the figure (right column). The pond contains 1000 m3 of liquid.... Figure 22.8 showed how an electroscope becomes negatively charged. The leaves will also repel each other if you touch the electroscope with a positively charged glass rod. Use a series of charge... The strong man is pulled in the three situations shown. Rank, from least to greatest, the amount of tension in the rope in his right hand (the one attached to the tree in B and C). A Itd Stand one domino upright so that when it topples, it hits two other upright dominos, each of which also hits two other upright dominos, and so forth. Arrange as many upright dominos as you can in... A cross-flow molecular filtration device equipped with a mesoporous membrane is used to separate the enzyme lysozyme from a fermentation broth, as shown in the figure (right column). Water at... What is the electric potential energy of the group of charges in FIGURE EX25.6? 1.0 nC 3.0 cm \ 3.0 cm 3.0 m -2.0 nC -2.0 nC FIGURE EX25.6 + Suppose a rubber ball collides head-on with a more massive steel ball traveling in the opposite direction with equal speed. Which ball, if either, receives the larger impulse? Explain. The nodal period of a satellite in a circular orbit of radius a and inclination i about the Earth is given by We are interested in predicting the time it will take for popcorn kernels to pop in a fluidized bed. The superficial air velocity inside the bed is 3 m/s, which is above the minimum fluidization... FIGURE P33.49 shows the interference pattern on a screen 1.0 m behind a diffraction grating. The wavelength of the light is 620 nm. How many lines per millimeter does the grating have? Intensity x... A student sitting on a stool that is free to rotate but is initially at rest, holds a bicycle wheel. The wheel has a rotational velocity of 5 rev/s about a vertical axis, as shown in the diagram. The... What diameter should the nichrome wire in FIGURE P27.63 be in order for the electric field strength to be the same in both wires? Nichrome Aluminum 1.0 mm diameter FIGURE P27.63 A bullet is fired horizontally with an initial velocity of 900 m/s at a target located 150 m from the rifle. a. How much time is required for the bullet to reach the target? b. Using the approximate... Larry leaves home at 9:05 and runs at constant speed to the lamppost seen in FIGURE EX2.3. He reaches the lamppost at 9:07, immediately turns, and runs to the tree. Larry arrives at the tree at 9:10.... A 4.0 10 10 kg asteroid is heading directly toward the center of the earth at a steady 20 km/s. To save the planet, astronauts strap a giant rocket to the asteroid perpendicular to its direction of... A 5.0-mm-diameter proton beam carries a total current of 1.5 mA. The current density in the proton beam, which increases with distance from the center, is given by J = J edge (r/R), where R is the...
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