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A composite wall is to be constructed of in. of stainless steel (k = 10 Btu/h ft F), 3 in. of cork board (k = 0.025 Btu/h ft F), and in. of plastic (k = 1.5 Btu/h ft F). Determine the thermal... A rectangular metal loop with 0.050 resistance is placed next to one wire of the RC circuit shown in FIGURE P30.52. The capacitor is charged to 20 V with the polarity shown, then the switch is... Water flows at a rate of 20 L/s through a horizontal pipe whose diameter is constant at 3 cm. The pressure drop across a valve in the pipe is measured to be 2 kPa, as shown in Fig P12??55. Determine... Hot engine oil with heat capacity rate of 4440 W/K (product of mass flow rate and specific heat) and an inlet temperature of 150C flows through a double pipe heat exchanger. The double pipe heat... Little Hudson holds the 10-kg barbell 0.3 m above the floor. (a) What is the PE of the barbell relative to the floor? (b) How much additional work will Hudson do when he lifts the barbell to a height... A hot-wire anemometer is a common instrument used to measure the velocity of a flowing gas. A typical probe tip is shown below. Electrical current is passed through a very thin wire of platinum or... A perfectly stirred tank is used to heat a flowing liquid. The dynamic model is shown in Fig. E14.4. Consider the ratio control scheme shown in Fig. 15.6. Each flow rate is measured using an orifice plate and a differential pressure (D/P) transmitter. The pneumatic output signals from the D/P... Two immiscible fluids are flowing down between two flat, infinitely long flat parallel plates as shown in the figure below. The plate on the left is moving down with a velocity of v A , and the plate... A computer graphics chip measures 5 cm on a side and is 3-mm thick. The chip consumes 15 W of power, which is dissipated as heat from the top side of the chip. A fan blows air over the surface of the... What are the electric fields at points 1, 2, and 3 in FIGURE P22.64? Give your answer in component form. 2.0 cm 5.0 nC +. 1.0 cm 2.0 cm FIGURE P22.64 A thin polymer film contains some residual solvent. It is desired to evaporate the volatile solvent (n-hexane, solute A) from the polymer using the process shown in the figure below. The wet polymer... A house with 200-m 2 floor space is to be heated with geothermal water flowing through pipes laid in the ground under the floor. The walls of the house are 4 m high, and there are 10 single-paned... Light of 630 nm wavelength illuminates two slits that are 0.25 mm apart. FIGURE EX33.5 shows the intensity pattern seen on a screen behind the slits. What is the distance to the screen? Intensity x... In Fig. Q9.4, all points on the chain have the same linear speed. Is the magnitude of the linear acceleration also the same for all points on the chain? How are the angular accelerations of the two... Six observed hadrons have the quantum numbers (Q, B, S, C, B) = (2, 1, 0, 1, 0), (0, 1,2, 1, 0), (0, 0, 1, 0,1), (0,1, 1, 0, 0), (0, 1,1, 1, 0) and (1, 1,3, 0, 0), respectively. Identify their quark... Air-track gliders with masses 300 g, 400 g, and 200 g are lined up and held in place with lightweight springs compressed between them. All three are released at once. The 200 g glider flies off to... a. Which point in Figure EX26.5, A or B, has a larger electric potential? b. What is the potential difference between A and B? E = 1000 V/m B. FIGURE EX26.5 7 cm 3 cm FIGURE Q12.3 shows three rotating disks, all of equal mass. Rank in order, from largest to smallest, their rotational kinetic energies K a to K c . 2w 2r FIGURE Q12.3 len It is desired to control the exit temperature T 2 of the heat exchanger shown in Fig. E11.18 by adjusting the steam flow rate w s . Unmeasured disturbances occur in inlet temperature T 1 . The... In lab tests on a 9.25-cm cube of a certain material, a force of 1375 N directed at 8.50° to the cube (Fig. E11.37) causes the cube to deform through an angle of 1.24°. What is the shear... The water at 20°C in a 10-m-diameter, 2-m-high aboveground swimming pool is to be emptied by unplugging a 5-cm-diameter, 25-m-long horizontal plastic pipe attached to the bottom of the pool.... A ball hangs from a string attached to the ceiling, as shown in the diagram. a. What forces act on the ball? How many are there? b. What is the net force acting on the ball? Explain. c. For each... The energy-level scheme for the hypothetical one electron element Searsium is shown in Fig. E39.25. The potential energy is taken to be zero for an electron at an infinite distance from the nucleus.... Rank in order, from largest to smallest, the electric potentials V a to V e at points a to e in FIGURE Q25.8. Explain. a b. + ++ + + + + + + + + + + +++ FIGURE Q25.8 A ceramic cube 3.0 cm on each side radiates heat at 630 W. At what wavelength, in mm, does its emission spectrum peak? Assume e = 1. Air-Bag Injuries. During an auto accident, the vehicles air bags deploy and slow down the passengers more gently than if they had hit the windshield or steering wheel. According to safety standards,... A heat engine using a diatomic gas follows the cycle shown in FIGURE P21.56. Its temperature at point 1 is 20°C. a. Determine W s , Q, and ÎE th for each of the three processes in this... Two water reservoirs of height h 1 = 60 m and h 2 = 30 m are connected by a pipe that is 0.35 m in diameter. The exit of the pipe is submerged at distance h 3 = 8 m from the reservoir surface. a.... A pendulum is formed from a small ball of mass m on a string of length L. As FIGURE CP10.69 shows, a peg is height h = L/3 above the pendulums lowest point. From what minimum angle θ... A process control system contains the following transfer functions: (a) Show how G O L (s) can be approximated by a FOPTD model; Find K,Ï, and θ for the open-loop process transfer... Suppose the monkey weighs 100 N and the vine supporting her pulls upward with a force of 120 N. What is the net force on the monkey? Describe her motion. Liquid nitrogen at 77 K is stored in a cylindrical container having an inside diameter of 25 cm. The cylinder is made of stainless steel and has a wall thickness of 1.2 cm. Insulation is to be added... The figure illustrates the operation of an air lift pump. Compressed air is forced into a perforated chamber to mix with the water so that the specific gravity of the airwater mixture above the air... A coated sheet is being dried with hot air blowing in cross flow on the sheet surface. The surface temperature of the sheet is constant at 90°C, while the air velocity and temperature are 0.3 m/s... If quantum mechanics replaces the language of Newtonian mechanics, why dont we have to use wave functions to describe the motion of macroscopic bodies such as baseballs and cars? A hot liquid is cooled by cold water in a counter-current heat exchanger: shown in Fig. E8.15: Temperature T h2 is to be controlled by adjusting flow rate, w c . The temperature sensor/transmitter... Design a steam power cycle that can achieve a cycle thermal efficiency of at least 40 percent under the conditions that all turbines have isentropic efficiencies of 85 percent and all pumps have... Consider the unusual piping diagram for the four tanks in Fig. E2.22 in which both the flow rates F 1 and F 2 are split between two streams entering the upper and lower tanks (denoted by the... A 1.75-cm diameter naphthalene mothball is suspended in an air stream at 280 K, 1.0 atm, and constant velocity of 1.4 m/s. Solid naphthalene exerts a vapor pressure of 2.8 Pa at 280 K. Consequently,... Consider the following transfer function: G(s)= Y(s) / U(s) = 3e s / 10s + 1 (a) What is the steady-state gain? (b) What is the time constant? (c) If U(s) = 4/s, what is the value of the output y(t)... The V-shaped tank has width w into the paper and is filled from the inlet pipe at volume flow Q. Derive expressions for (a) the rate of change dh/dt and (b) the time required for the surface to rise... The hot water needs of a household are to be met by heating water at 55°F to 200°F by a parabolic solar collector at a rate of 4 lbm/s. Water flows through a 1.25-in-diameter thin aluminum... In Example 13.5 (Section 13.3) we ignored the gravitational effects of the moon on a spacecraft en route from the earth to the moon. In fact, we must include the gravitational potential energy due to... A 13 cm by 13 cm steel angle with the dimensions shown is attached to a wall with a surface temperature of 600 K. The surrounding air is at 300 K, and the convective heat-transfer coefficient between... A vertical aerial photograph reveals a tall building. The foot of one corner of the building has (x, y) coordinates (30.5, 62.0) (both measured in mm from the lower left-hand corner of the negative),... The distillation column in Fig. 15.8 has the following transfer function model: with G v = G m = G t = 1. (a) Design a feedforward controller based on a steady-state analysis. (b) Design a... A block on a frictionless table is connected as shown in FIGURE P15.74 to two springs having spring constants k 1 and k 2 . Show that the blocks oscillation frequency is given by f = f 1 2 + f 2 2... A uniform volume charge density of 80 C/m 3 is present throughout the region 8 mm < r < 10 mm. Let = 0 for 0 < r < 8 mm. (a) Find the total charge inside the spherical surface r = 10 mm. (b) Find... A shell-and-tube heat exchanger with 2-shell passes and 8-tube passes is used to heat ethyl alcohol (c p = 2670 J/kg·K) in the tubes from 25°C to 70°C at a rate of 2.1 kg/s. The... Air at 10°C enters a 12-cm-diameter and 5-m-long pipe at a rate of 0.065 kg/s. The inner surface of the pipe has a roughness of 0.22 mm, and the pipe is nearly isothermal at 50°C. Determine... Figure CP19.79 shows a thermodynamic process followed by 0.015 mol of hydrogen. How much heat energy is transferred to the gas? p (atm) 2- -V (cm) 300 100 200 FIGURE CP19.79 A steel block with a density of 7800 kg/m 3 is suspended from a string in a beaker of water so that the block is completely submerged but not resting on the bottom. The block is a cube with sides of... A coolant (specific gravity = 1.2) is pumped through a heat exchanger and control valve at a nominal (desired) flow rate of q d = 0.6 m 3 /min. The total pressure drop over this heat exchanger system... Oil (sp. gr. = 0.8) flows smoothly through the circular reducing section shown at 3 ft 3 /s. If the entering and leaving velocity profiles are uniform, estimate the force that must be applied to the... a. A cylindrical tank of radius R, filled to the top with a liquid, has a small hole in the side, of radius r, at distance d below the surface. Find an expression for the volume flow rate through the... A heat engine using a monatomic gas follows the cycle shown in FIGURE P21.58. a. Find W s , Q, and E th for each process in the cycle. Display your results in a table.b. What is the thermal... Suzie Skydiver with her parachute has a mass of 50 kg. (a) Before opening her chute, what force of air resistance will she encounter when she reaches terminal velocity? (b) What force of air... Consider a 50-cm-diameter and 95-cm-long hot water tank. The tank is placed on the roof of a house. The water inside the tank is heated to 80C by a flat-plate solar collector during the day. The tank... A 10.0 nC charge is located at position (x, y) = (1.0 cm, 2.0 cm). At what (x, y) position(s) is the electric field a. -225,000 i N/C? b. (161,000 i + 80,500 j) N/C? c. (21,600 i - 28,800 j) N/C? Tubular membranes of silicone rubber can be used for bubble less aeration of water. A cross section of the tube is shown in the figure (right-hand column). Pure oxygen (O 2 ) gas is pressurized to... A double-pipe, counter current heat exchanger is used to cool saturated steam at 2 bar (T s = 120C) to a saturated liquid. At this temperature and pressure, the inlet volumetric flow rate of steam is... The two springs in FIGURE P29.72 each have a spring constant of 10 N/m. They are compressed by 1.0 cm when a current passes through the wire. How big is the current? www 20 cm www. B=0.5 T FIGURE... A 3.0-m-long ladder, as shown in Figure 12.35, leans against a frictionless wall. The coefficient of static friction between the ladder and the floor is 0.40. What is the minimum angle the ladder can... A 0.2-m-wide plate, 0.8 m long, is placed on the bottom of a shallow tank. The plate is heated, and maintained at a constant surface temperature of 60°C. Liquid water 12 cm deep flows over the... A small, square loop carries a 25 A current. The on-axis magnetic field strength 50 cm from the loop is 7.5 nT. What is the edge length of the square? FIGURE P23.38 shows three charges at the corners of a square. Write the electric field at point P in component form. -Q FIGURE P23.38 PO- Consider the liquid storage tank with a low-level inter-lock, as shown in Fig. 10.4. Suppose that an independent low-level alarm is added, with its set-point value above the value for the low-level... Thick fluids such as asphalt and waxes and the pipes in which they flow are often heated in order to reduce the viscosity of the fluids and thus to reduce the pumping costs. Consider the flow of such... A small spherical bead is used as a controlled drug release capsule in the gastrointestinal system (i.e., your stomach). In this particular case, a 0.10-cm diameter bead has a uniform initial... A mass-transfer process is used to remove ammonia (NH 3 , solute A) from a mixture of NH 3 and air, using water as the absorption solvent. At the present conditions of operation, the partial pressure... Consider the catalytic reaction process shown in the figure below. The control volume has two catalytic zones: a porous catalyst (catalyst I) that fills the control volume, and a nonporous catalyst... A wave pulse on a string has the dimensions shown in Fig. E15.30 at t = 0. The wave speed is 40 cm/s. (a) If point O is a fixed end, draw the total wave on the string at t = 15 ms, 20 ms, 25 ms, 30... Figure E3.3 shows a pulse function,u(t). (a) From the information shown in Fig. 3.3, calculate the pulse width, t w . (b) Express u(t) as the sum of simpler functions (some perhaps translated in... For what electric field strength would the current in a 2.0 mm-diameter nichrome wire be the same as the current in a 1.0-mm-diameter aluminum wire in which the electric field strength is 0.0080 V/m? A 110 Hz source of emf has a peak voltage of 50 V. Draw the emf phasor at t = 3.0 ms. An additive process model is depicted in the figure below. For (unit impulse) (a) Derive the response Y(s) and describe y(t) quantitatively. (b) Simulate the response and identify its major... A light bulb glows because it has resistance. The brightness of a light bulb increases with the electrical power dissipated in the bulb. (a) In the circuit shown in Fig. Q25.14a, the two bulbs A and... Consider the process shown in the figure. A bulk gas stream containing 0.10 mole% of carbon monoxide (CO) gas, 2.0 mole% O 2 gas, and 97.9 mole% of CO 2 gas flows over a flat catalytic surface of... You are testing a small flywheel (radius 0.166 m) that will be used to store a small amount of energy. The flywheel is pivoted with low friction bearings about a horizontal shaft through the... A diving bell is a 3.0-m-tall cylinder closed at the upper end but open at the lower end. The temperature of the air in the bell is 20C. The bell is lowered into the ocean until its lower end is 100... FIGURE P24.38 shows a solid metal sphere at the center of a hollow metal sphere. What is the total charge on (a) The exterior of the inner sphere, (b) The inside surface of the hollow sphere, (c) The... A bird grabs a clam, carries it in its beak to a considerable height, and then drops it on a rock below, breaking the clam shell. Describe the energy conversions that take place in this process. A 55 kg softball player slides into second base, generating 950 J of thermal energy in her legs and the ground. How fast was she running? Consider the cylindrical shaped absorbent material designed to selectively remove solute A from solution. The uptake of solute A through the homogeneous absorbent material is limited by the molecular... You are designing a pendulum for a science museum. The pendulum is made by attaching a brass sphere with mass m to the lower end of a long, light metal wire of (unknown) length L. A device near the... The response of a system to a unit step change in the input (occurring at time 0) is shown in Fig. E7.11. (a) Derive a second-order plus time delay model approximation for the system. Provide values... Two blocks tied together by a horizontal string are being pulled across the table by a horizontal force of 30 N as shown. The 2-kg block has a 6-N frictional force exerted on it by the table, and the... A hot stage for a manufacturing process is shown in the accompanying figure, where a slab of stainless steel is mounted on top of an electrical resistance heater. The stainless steel slab is 20 cm... Figure P19.62 shows a thermodynamic process followed by 120 mg of helium. a. Determine the pressure (in atm), temperature (in C), and volume (in cm 3 ) of the gas at points 1, 2, and 3. Put your... Two equal-mass blocks are connected by a length of string. One block is placed at rest on a very smooth table, and the other block dangles off the tables edge. You hold the blocks so they dont move.... FIGURE P13.35 shows three masses. What are the magnitude and the direction of the net gravitational force on? (a) The 20.0 kg mass (b) The 5.0 kg mass?? Give the direction as an angle cw or ccw from... The water level in a tank is 34 ft above the ground. A hose is connected to the bottom of the tank at the ground level and the nozzle at the end of the hose is pointed straight up. The tank cover is... A stream becomes a river as it moves downgradient. Give the sequence in which the following appear in the evolution of a stream: (a) Meandering pattern, (b) Rapids, (c) Delta. What is the line integral of B between points i and f in FIGURE EX29.21? (cm) 50- - Integration path B= 0.10 T x () 50 FIGURE EX29.21 Two parallel disks of diameter D = 3 ft separated by L = 2 ft are located directly on top of each other. The disks are separated by a radiation shield whose emissivity is 0.15. Both disks are black... A current filament carrying I in the a z direction lies along the entire positive z axis. At the origin, it connects to a conducting sheet that forms the xy plane. (a) Find K in the conducting sheet.... If we model the vibrating system as a mass on a spring, what is the mass necessary to achieve the desired resonant frequency when the tip is not interacting with the surface? (a) 25 ng; (b) 100 ng;... A sky diver has a weight of 750 N. Suppose that the air resistive force acting on the diver increases in direct proportion to his velocity such that for every 10 m/s that the divers velocity... A monatomic gas fills the left end of the cylinder in Figure CP19.82. At 300 K, the gas cylinder length is 10.0 cm and the spring is compressed by 2.0 cm. How much heat energy must be added to the...
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