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Engine oil with properties given below flows at a rate of 136 kg per hour through a 7.5-cm-ID pipe whose inside surface is maintained at 100°C. If the oil enters at 160°C, what will its... A room measuring 12 ft by 20 ft by 8 ft high has its floor and ceiling temperatures maintained at 85F and 65F, respectively. Assuming the walls to be re-radiating and all surfaces to have an... A gray, diffuse circular heater with a diameter of 15 cm is placed parallel to a second gray, diffuse receiver with a spacing of 7.5 between them. The backs of both surfaces are insulated and... Starting with the Ficks rate equation for the diffusion of A through a binary mixture of components A and B, given by Show that and state all assumptions needed to arrive at this result. NA =... The general form of the StefanMaxwell equation for mass transfer of species i in an n-component ideal gas mixture along the z-direction for flux is given by Show that for a gas-phase binary mixture... Derive Equation 26.33 for the induced surface charge density on the dielectric in a capacitor. Equation 26.33 nol 1 Ninduced The chemical vapor deposition of silane vapor (SiH 4 ) forms a thin film of solid silicon as described in example 1, Chapter 25. Consider that the simplified CVD unit shown in Figure 25.5 is... Microvia are microscopic passages between two thin films on a microelectronic device. Often, microvia are filled with a conductive metal to make a microscopic conductor for the flow of electrons... Aluminum is the primary conductor material for fabrication of microelectronic devices. Consider the composite thin film shown in the figure below. A thin film of solid aluminum is sputter-coated onto... We are interested in the diffusion of CO 2 gas out of a randomly porous adsorbent material slab of 2.0 cm thickness, as shown in the figure below. Initially, the gas space inside the porous material... Consider a rectangular-shaped gel tablet of thickness 0.652 cm and width 1.0 cm loaded with the drug Dramamine. The edges of the gel tablet are sealed so that diffusion of Dramamine occurs only along... The table below presents equilibrium distribution data for four gaseous solutes dissolved in water, using air as the carrier gas: a. Using a spreadsheet to perform the calculations, prepare a graph... The two blocks in FIGURE P7.34 are sliding down the incline. What is the tension in the massless string? 1.0 kg 2.0 kg Hx = 0.20 Hy =0.10 20 FIGURE P7.34 A packed-bed tower is used for absorption of sulfur dioxide (SO 2 ) from an air stream using water as the solvent. At one point in the tower, the composition of SO 2 is 10% (by volume) in the gas... A biosensor is a device that uses a biological mechanism to aid in the detection of a solute (A) within a mixture. Consider the hemispherical-shaped biosensor tip shown in the figure on page 529. The... ASAR operates at a frequencyof 5.3GHz. Its satellite platformis 775kmabove the Earths surface and has a speed relative to the surface of 6.73 kms -1 . The swath width is 100 km and the incidence... The NASA Team algorithm for calculating sea-ice concentration from SSM/I data defines the polarisation ratio PR as and thegradient ratioGR as where, in both of these expressions,T fP represents the... A 25 g string is under 20 N of tension. A pulse travels the length of the string in 50 ms. How long is the string? How many atoms are in a 2.0 cm 2.0 cm 2.0 cm cube of aluminum? Why must the wave function of a particle be normalized? A plastic rod is charged to -12 nC by rubbing. a. Have electrons been added to the rod or protons removed? b. How many electrons have been added or protons removed? The net force on the 1.0 nC charge in FIGURE P22.48 is zero. What is q? 1.0 nC +. 4.0 cm 2.0 cm + 2.0 nC 2.0 nC (+ 3.0 cm 3.0 cm FIGURE P22.48 FIGURE EX24.17 shows three charges. Draw these charges on your paper four times. Then draw two-dimensional cross sections of three-dimensional closed surfaces through which the electric flux is (a)... a. What is the magnitude of the torque on the current loop in FIGURE EX29.40? b. What is the loops equilibrium orientation? 2.0 cm |2.0 mm - Wire 2.0 A 0.20 A FIGURE EX29.40 FIGURE Q33.6 shows the light intensity on a viewing screen behind a circular aperture. What happens to the width of the central maximum if a. The wavelength of the light is increased?b. The diameter... The weight of a water tank open to the atmosphere is balanced by a counterweight, as shown in Fig. P13??41. There is a 4-cm hole at the bottom of the tank with a discharge coefficient of 0.90, and... A 90? elbow in a horizontal pipe is used to direct water flow upward at a rate of 40 kg/s. The diameter of the entire elbow is 10 cm. The elbow discharges water into the atmosphere, and thus the... Air enters a 10-m-long section of a rectangular duct of cross section 15 cm 20 cm made of commercial steel at 1 atm and 35?C at an average velocity of 7 m/s. Disregarding the entrance effects,... Oil with a density of 850 kg/m 3 and kinematic viscosity of 0.00062 m 2 /s is being discharged by a 8-mm-diameter, 40-m-long horizontal pipe from a storage tank open to the atmosphere. The height of... The water needs of a small farm are to be met by pumping water from a well that can supply water continuously at a rate of 4 L/s. The water level in the well is 20 m below the ground level, and water... An engineer proposes to use the mass-transfer equipment shown in the figure (next page) to prepare a water stream containing dissolved oxygen. Liquid water containing no dissolved oxygen is fed to... A spherical pellet containing pure solid A is suspended in a flowing liquid stream at 20C. The initial diameter of the pellet is 1.0 cm, and the bulk liquid velocity is 10.0 cm/s. Component A is... A wind turbine with two or four hollow hemispherical cups connected to a pivot is commonly used to measure wind speed. Consider a wind turbine with four 8-cm-diameter cups with a center-to-center... A DC motor delivers mechanical power to a rotating stainless steel shaft (k = 15.1 W/m·K) with a length of 25 cm and a diameter of 25 mm. In a surrounding with ambient air temperature of... Consider an aircraft that takes off at 260 km/h when it is fully loaded. If the weight of the aircraft is increased by 10 percent as a result of overloading, determine the speed at which the... Consider a 5-m-high, 8-m-long, and 0.22-m-thick wall whose representative cross section is as given in the figure. The thermal conductivities of various materials used, in W/m·K, are k A = k F... A furnace is shaped like a long equilateral-triangular duct where the width of each side is 2 m. Heat is supplied from the base surface, whose emissivity is 1 = 0.8, at a rate of 800 W/m 2 while the... Oil in an engine is being cooled by air in a crossflow heat exchanger, where both fluids are unmixed. Oil (c ph = 2047 J/kg·K) flowing with a flow rate of 0.026 kg/s enters the tube side at... Consider a water-to-water counter-flow heat exchanger with these specifications. Hot water enters at 95°C while cold water enters at 20°C. The exit temperature of hot water is 15°C... In Section 6.2.2 we assumed that the combined spacespin wave function of a baryon was symmetric under the interchange of any pair of like quarks. What spectrum of low-lying baryon states composed of... List the independent, continuously variable parameters of the standard model, whose values must be determined from experiment. How many are there in total? Draw the dominant Feynman diagrams for the reaction e + + e e + e . Estimate the order of magnitude and energy dependence of the corresponding contributions to the total cross-section for... Estimate the branching ratios for the four-lepton decays (10.58) and (10.60) of the Higgs boson by relating them to the branching ratios for other reactions listed in Table 10.1. Use your answers to... Show that when an impulse produced by a 12-N force acts over 2.0 s on an ice puck initially at rest on an air table, the change in momentum is 24 kg m/s. Work = force distance; W = Fd How much energy would a 100 W light bulb consume if left on for 10 hours? Relate eq.(2.20)?? to eq. (2.9) and compute g in terms of G, M ? , R ? as described in the text. GMm V (r) = Review how magnetic fields are calculated from Ampere?s law by computing? (a) the magnetic field due to a straight wire? (b) the magnetic field in the interior of a very long solenoid.? The contours... Compute the maximum energy flux possible for electromagnetic waves in air given the constraint that the electric field cannot exceed the breakdown field. A wave travels to the right on a string with constant tension and a mass density that slowly increases from on the far left to on the far right. The mass density changes slowly enough that its... Quantitatively compare the Carnot Rankine cycle of Figure 13.12(a) with the ideal Rankine cycle of Figure 13.12(b) Compare efficiencies and the work done per cycle. All the necessary information... To get a sense of the potential practical relevance for energy purposes of one aspect of as-yet-undiscovered physics, consider proton decay. Making the most general assumptions about the nature of... A particle of mass m and energy E encounters a triangular barrier of width 2w and height V 0 (see Figure 15.6) Estimate the probability that it will tunnel through the barrier. How does the... (a)? Derive the large A approximation to the logarithmic energy decrement given in eq. (18.5) (b) Show that the number of collisions with a nucleus with atomic mass A required to decrease the energy... To a first approximation for computing stopping power, living tissue can be approximated as water. Using data on the range of protons in water, estimate the energy of a proton required to place its... Consider a situation in which, through accident or ill-intention, all the spent nuclear fuel from a years operation of a 1 GWe light water reactor were uniformly distributed across one square... Consider building a wind turbine at a wind power class 5 site. Assume that the hub height is 50 m and the blade length is 15 m, and that the turbine operates at 50% of the maximum theoretical... Angel Falls in Venezuela, at a height of 979 m, is the highest waterfall in the world. Ignoring air resistance, how much warmer is the water at the bottom of the falls, where the kinetic energy it... Compare land use of hydropower to solar power by computing the ratio of power output to reservoir surface area for the Three Gorges Dam (maximum capacity 22500 MW, reservoir area 1084 km 2 ) and the... If a horseshoe is heated in a blacksmiths furnace until it glows red hot, does the mass of the horseshoe change? If a spring is stretched to twice its equilibrium length, has its mass been altered in... A runner traveling with an initial velocity of 2.0 m/s accelerates at a constant rate of 1.2 m/s 2 for a time of 2 seconds. a. What is his velocity at the end of this time? b. What distance does the... Compute the time to melt 3000 m thickness of ice if there is an extra 5% of 200 W/m 2 average daily insolation for four months out of the year beyond the insolation that would give an ablation rate... A pirate map indicates that a treasure is buried 50 paces due east and 120 paces due north of a big rock. Will you know where to dig? Explain. A 150-g quantity of a certain metal, initially at 120C, is dropped into an insulated beaker containing 100 g of water at 20C. The final temperature of the metal and water in the beaker is measured as... A wave pulse is transmitted down a Slinky, but the Slinky itself does not change position. Does a transfer of energy take place in this process? Explain. What does the color of a star tell you about the star? Describe in words how you would compute the coefficient of performance for an ideal vapor-compression cycle working between temperatures T + and T - . Assume that you have data on the thermodynamic... Given four materials, with band gaps 0.2 eV, 0.7 eV, 1.5 eV, and 3 eV, which two are likely to make the best double-junction solar cell? Explain your answer. Consider parallel flow over a flat plate for air at 300 K and engine oil at 380 K. The free stream velocity is u = 2 m/s. The temperature difference between the surface and the free stream is the... The immobilized enzyme layer shown in the figure below is designed to convert substrate A to product B according to the simplified reaction A B with simplified rate equation R A = kc A . In this... As society searches for technical solutions to global warming, vast ponds of photosynthetic algae are seen as one possible solution for the removal of CO 2 from combustion of fossil fuels. Consider... The photocatalytic tubular reactor shown in the figure (next page) is used to decompose organic contaminants in liquid waste water. The inter walls of the 1.5 cm inner diameter glass tube are lined... The electron-positron pair that was discussed in Chapter 2 can form a hydrogenlike system called positronium. Calculate (a) The energies of the three lowest states and (b) The wavelength of the Lyman... An electron is in the ground state with energy E n of a one-dimensional infinite well with L = 10 -10 m. Compute the force that the electron exerts on the wall during an impact on either wall. In a region of space, a particle has a wave function given by (x) = Ae -x2/2L 2 and energy 2 /2mL 2 , where L is some length. (a) Find the potential energy as a function of x, and sketch V versus... A fence post is 52.0 m from where you are standing, in a direction 37.0 o north of east. A second fence post is due south from you. What is the distance of the second post from you, if the distance... For the hydraulic lift shown in Fig. 12.7, what must be the ratio of the diameter of the vessel at the car to the diameter of the vessel where the force F 1 is applied so that a 1520-kg car can be... For the equation, Use the partial fraction method, to find y(t). + 5 + 6y(t) = 7, (0) = 0, y(0) = 1 Find the Laplace transforms of the following functions, using the information in Table 3.1. (However, some of the individual terms in these functions may not have Laplace transforms.) (a) f(t) = 5 +... The dynamic model for a process is given by where u(t) is the input function and y(0) and dy/dt (0) are both zero. What are the functions of the time (e.g., e t/Ï ) in the solution for each of... The dynamic model between an output variable y and an input variable u can be expressed by (a) Does this system exhibit an oscillatory response after an arbitrary change in u? (b) What is the... Show that the diffuse albedo for specular reflection of perpendicularly polarised radiation and confirm that this expression has the correct limiting forms as the refractive index n tends to 1 and to... A heater for a semiconductor wafer has first-order dynamics, that is, the transfer function relating changes in temperature T to changes in the heater input power level P is where K has units [ C/Kw]... An aerial photographic system is used for stereophotography. The film negative is a square of sides, the focal length is f, the baseline is band the photographs (which are acquired with the camera... A single-tank process has been operating for a long period of time with the inlet flow rate q i equal to 30.1 ft 3 /min. After the operator increases the flow rate suddenly at t = 0 by 10%, the... Consider the simulation results for PID control in Figs. 8.15 and 8.16. Note that the u I response in Fig. 8.16 changes monotonically. Do you think this feature is typical of u I responses for other... A control system has the following transfer functions in its block diagram (see Fig. 11.8): G c =1, G v = 2, G d = G p = 2 / s(s + 4), G m = 1. For a unit step change in Y sp , determine (a) Y(s) / Y... Derive and sketch the complete small-signal equivalent circuit for a bipolar transistor at I C = 0 . 2 mA, V CB = 3V, V CS = 4 V. Device parameters are C je 0 = 20 fF, C 0 = 10 fF, C cs 0 = 20 fF, ... A passive microwave radiometer operating at 37 GHz has an effective area of 0.3 m 2 , and can detect a change of 0.9 K in its antenna temperature. It is operated from an altitude of 800 km to observe... A satellite is in a circular sun-synchronous orbit with an inclination of 98.2. It makes exactly 233 orbits of the Earth in exactly 16 days, and crosses the equator southbound at 0930h local time.... A radar transmits a power of 4 kW at a wavelength of 5 cm and over a range of 800 km. If the radar can detect a received signal of 10 - 16 W, calculate the required gain of the antenna, and hence... Prove Equation (8.16). Equation 8.16 dP, P,(t+2(h H)/c)f(h)dh dt 0- A radar altimeter emits a pulse whose variation of power with time is Gaussian with a length of 3.00 ns between 1/e points. The pulse is reflected from a surface whose height distribution is Gaussian... A very simplified model of the radar back scattering coefficient of a sea surface is 0 = A + Bcos 2 where is the angle between the wind direction and the radar look azimuth, and A and B are as... A chirp signal, in which the angular frequency rises uniformly from Ï 0 ÎÏ/2 to Ï 0 + ÎÏ/2 over a time T, can be written as exp(iÏ(t)), where the phase Ï(t)... For microwave radiation propagating vertically through the Earths atmosphere, the delay to a pulse as a result of the dry component of the atmosphere, expressed as an equivalent distance, is 2.33... Use the data of Table 7.1 to show that the effective area of a rectangular or circular paraboloidal antenna is roughly equal to its geometrical area. Table 7.1 HPBW (degrees) D (dB) Antenna type... The surfaces = 3, = 5, = 100, = 130, z = 3, and z = 4.5 define a closed surface. Find (a) The enclosed volume; (b) the total area of the enclosing surface; (c) The total length of the twelve... Use the Poisson sum formula to obtain the Fourier series of the signal 4m x (t) = m - (a) Use the Fourier transform of x(t) = exp (-t) u (t) - exp (t) u (-t) where > 0 (b) Use the result above and the relation u(t) = 1/2[sgn (t) + 1] to find Fourier transform of the unit step. (c)... Using the results given in Table 2.1 for the Fourier coefficients of a pulse train, plot the double-sided amplitude and phase spectra for the wave forms shown in Figure 2.34. (Note that x b (t) = -x...
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