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Scientists in the laboratory create a uniform electric field E =1.0 10 6 kn V/m in a region of space where B = 0. What are the fields in the reference frame of a rocket traveling in the positive... A rocket zooms past the earth at v = 2.0 10 6 m/s. Scientists on the rocket have created the electric and magnetic fields shown in FIGURE EX31.5. What are the fields measured by an earthbound... A laser beam is incident on the left mirror in FIGURE EX34.8. Its initial direction is parallel to a line that bisects the mirrors. What is the angle Ï of the reflected laser beam? 80 FIGURE... A 1.0-cm-thick layer of water stands on a horizontal slab of glass. A light ray in the air is incident on the water 60 from the normal. What is the rays direction of travel in the glass? The glass core of an optical fiber has an index of refraction 1.60. The index of refraction of the cladding is 1.48. What is the maximum angle a light ray can make with the wall of the core if it is... A camera has a circular aperture immediately behind the lens. Reducing the aperture diameter to half its initial value will A. Make the image blurry. B. Cut off the outer half of the image and leave... An object is 60 cm from a screen. What are the radii of a symmetric converging plastic lens (i.e., two equally curved surfaces) that will form an image on the screen twice the height of the object? Two immiscible Newtonian liquids flow steadily between two large parallel plates under the influence of an applied pressure gradient. The lower plate is fixed while the upper one is pulled with a... Water enters a centrifugal pump axially at atmospheric pressure at a rate of 0.09 m 3 /s and at a velocity of 5 m/s, and leaves in the normal direction along the pump casing, as shown in Fig.... Water is flowing through a 10-cm-diameter water pipe at a rate of 0.1 m 3 /s. Now a diffuser with an outlet diameter of 20 cm is bolted to the pipe in order to slow down water, as shown in Fig.... Consider steady developing laminar flow of water in a constant-diameter horizontal discharge pipe attached to a tank. The fluid enters the pipe with nearly uniform velocity V and pressure P 1 . The... An incompressible fluid of density and viscosity flows through a curved duct that turns the flow 180?. The duct cross-sectional area remains constant. The average velocity, momentum flux correction... A constant-velocity horizontal water jet from a stationary nozzle impinges normally on a vertical flat plate that rides on a nearly frictionless track. As the water jet hits the plate, it begins to... A horizontal water jet from a nozzle of constant exit cross section impinges normally on a stationary vertical flat plate. A certain force F is required to hold the plate against the water stream. If... A horizontal 5-cm-diameter water jet with a velocity of 18 m/s impinges normally upon a vertical plate of mass 1000 kg. The plate rides on a nearly frictionless track and is initially stationary.... A 100-ft 3 /s water jet is moving in the positive x-direction at 18 ft/s. The stream hits a stationary splitter, such that half of the flow is diverted upward at 45? and the other half is directed... Explain the importance of the Reynolds transport theorem in fluid mechanics, and describe how the linear momentum equation is obtained from it. A pressurized tank of water has a 10-cm-diameter orifice at the bottom, where water discharges to the atmosphere. The water level is 2.5 m above the outlet. The tank air pressure above the water... An airplane is flying at an altitude of 12,000 m. Determine the gage pressure at the stagnation point on the nose of the plane if the speed of the plane is 300 km/h. How would you solve this problem... An oil pump is drawing 25 kW of electric power while pumping oil with r = 860 kg/m 3 at a rate of 0.1 m 3 /s. The inlet and outlet diameters of the pipe are 8 cm and 12 cm, respectively. If the... Air at 105 kPa and 37?C flows upward through a 6-cm-diameter inclined duct at a rate of 65 L/s. The duct diameter is then reduced to 4 cm through a reducer. The pressure change across the reducer is... How is the location of the hydraulic grade line determined for open-channel flow? How is it determined at the outlet of a pipe discharging to the atmosphere? The water level in a tank is 20 m above the ground. A hose is connected to the bottom of the tank, and the nozzle at the end of the hose is pointed straight up. The tank is at sea level, and the... (a) What is the speed of a proton that has total energy 1000 GeV? (b) What is the angular frequency Ï of a proton with the speed calculated in part (a) in a magnetic field of 4.00 T? Use both... Consider laminar flow of a fluid through a square channel with smooth surfaces. Now the average velocity of the fluid is doubled. Determine the change in the head loss of the fluid. Assume the flow... Repeat Prob. 1437 for turbulent flow in smooth pipes for which the friction factor is given as f = 0.184Re -0.2. What would your answer be for fully turbulent flow in a rough pipe? Consider flow from a water reservoir through a circular hole of diameter D at the side wall at a vertical distance H from the free surface. The flow rate through an actual hole with a sharp-edged... A 2.4-m-diameter tank is initially filled with water 4 m above the center of a sharp-edged 10-cm-diameter orifice. The tank water surface is open to the atmosphere, and the orifice drains to the... A 2.0-cm-tall object is 20 cm to the left of a lens with a focal length of 10 cm. A second lens with a focal length of 15 cm is 30 cm to the right of the first lens. a. Use ray tracing to find the... A camera takes a properly exposed photo at f/5.6 and 1/125 s. What shutter speed should be used if the lens is changed to f/4.0? Your task in physics laboratory is to make a microscope from two lenses. One lens has a focal length of 2.0 cm, the other 1.0 cm. You plan to use the more powerful lens as the objective, and you want... A laboratory experiment shoots an electron to the left at 0.90c. What is the electrons speed, as a fraction of c, relative to a proton moving to the right at 0.90c? Determine: a. The speed of a 300 eV electron. b. The speed of a 3.5 MeV H+ ion. c. The specific type of particle that has 2.09 MeV of kinetic energy when moving with a speed of 1.0 10 7 m/s. Electrons, all with the same speed, pass through a tiny 15 nm-wide slit and create a diffraction pattern on a detector 50 mm behind the slit. What is the electrons kinetic energy, in eV, if the... Consider the electron wave function where x is in cm. a. Determine the normalization constant c. b. Draw a graph of Ï(x) over the interval -2 cm ¤ x ¤ 2 cm. Provide numerical... Consider the electron wave function a. Determine the normalization constant c. Your answer will be in terms of L.b. Draw a graph of (x) over the interval -L ?? x ?? 2L.c. Draw a graph of |(x)| 2 over... Consider the electron wave function where x is in nm.a. Determine the normalization constant c.b. Draw a graph of (x) over the interval -5 nm ?? x ?? 5 nm. Provide numerical scales on both axes.c.... A particle confined in a rigid one-dimensional box of length 10 fm has an energy level E n = 32.9 MeV and an adjacent energy level E n+1 = 51.4 MeV. a. Determine the values of n and n + 1. b. Draw an... Consider a particle in a rigid box of length L. For each of the states n = 1, n = 2, and n = 3: a. Sketch graphs of |(x)| 2 . Label the points x = 0 and x = L. b. Where, in terms of L, are the... The incident voltage wave on a certain lossless transmission line for which Z 0 = 50 and p = 2 10 8 m/s is V + (z, t) = 200 cos(t z) V. (a) Find . (b) Find I + (z, t). The section of line for... In a laminar flow through a circular tube of radius of R, the velocity and temperature profiles at a cross section are given by u = u 0 (1 - r 2 /R 2 ) and T(r) = A + Br 2 - Cr 4 where A, B and C are... In a meat processing plant, 2-cm-thick steaks (k = 0.45 W/mK and = 0.91 10 -7 m 2 /s) that are initially at 25C are to be cooled by passing them through a refrigeration room at -11C. The heat... Two water reservoirs A and B are connected to each other through a 40-m-long, 2-cm-diameter cast iron pipe with a sharp-edged entrance. The pipe also involves a swing check valve and a fully open... A certain part of cast iron piping of a water distribution system involves a parallel section. Both parallel pipes have a diameter of 30 cm, and the flow is fully turbulent. One of the branches (pipe... A spherical vessel, 3.0 m in diameter (and negligible wall thickness), is used for storing a fluid at a temperature of 0C. The vessel is covered with a 5.0-cm-thick layer of an insulation (k = 0.20... A submarine can be treated as an ellipsoid with a diameter of 5 m and a length of 25 m. Determine the power required for this submarine to cruise horizontally and steadily at 40 km/h in seawater... Two pin fins are identical, except that the diameter of one of them is twice the diameter of the other. For which fin is the (a) fin effectiveness (b) fin efficiency higher? Explain. A 4-mm-diameter and 10-cm-long aluminum fin (k = 237 W/m·K) is attached to a surface. If the heat transfer coefficient is 12 W/m 2 ·K, determine the percent error in the rate of heat... How does the overall effectiveness of a finned surface differ from the effectiveness of a single fin? During steady motion of a vehicle on a level road, the power delivered to the wheels is used to overcome aerodynamic drag and rolling resistance (the product of the rolling resistance coefficient and... Spherical glass beads coming out of a kiln are allowed to cool in a room temperature of 30°C. A glass bead with a diameter of 10 mm and an initial temperature of 400°C is allowed to cool for... Consider a cubic block whose sides are 5 cm long and a cylindrical block whose height and diameter are also 5 cm. Both blocks are initially at 20°C and are made of granite (k = 2.5 W/m·K... Consider heat conduction through a wall of thickness L and area A. Under what conditions will the temperature distributions in the wall be a straight line? Steel rods, 2 m in length and 60 mm in diameter, are being drawn through an oven that maintains a temperature of 800°C and convection heat transfer coefficient of 128 W/m 2 ·K. The steel... The local atmospheric pressure in Denver, Colorado (elevation 1610 m) is 83.4 kPa. Air at this pressure and at 25C flows with a velocity of 9 m/s over a 2.5-m 5-m flat plate. Determine the drag... Hot exhaust gases leaving a stationary diesel engine at 450C enter a l5-cm-diameter pipe at an average velocity of 4.5 m/s. The surface temperature of the pipe is 180C. Determine the pipe length if... A long Pyroceram rod (Ï = 2600 kg/m 3 , c p = 808 J/kg·K, k = 3.98 W/m·K, and α = 1.89 à 10 6 m 2 /s) with diameter of 10 mm has an initial uniform temperature... A 10-cm thick aluminum plate (Ï = 2702 kg/m 3 , c p = 903 J/kg·K, k = 237 W/m·K, and α = 97.1 à 10 6 m 2 /s) is being heated in liquid with temperature of... A long aluminum wire of diameter 3 mm is extruded at a temperature of 280°C. The wire is subjected to cross air flow at 20°C at a velocity of 6 m/s. Determine the rate of heat transfer from... Steam in a heating system flows through tubes whose outer diameter is 5 cm and whose walls are maintained at a temperature of 180°C. Circular aluminum alloy 2024-T6 fins (k = 186 W/m·K) of... Parallel plates form a solar collector that covers a roof, as shown in the figure. The plates are maintained at 15°C, while ambient air at 10°C flows over the roof with V = 2 m/s. Determine... Light oil at 75F flows over a 22-ft-long flat plate with a free-stream velocity of 6 ft/s. Determine the total drag force per unit width of the plate. Air at 25C and 1 atm is flowing over a long flat plate with a velocity of 8 m/s. Determine the distance from the leading edge of the plate where the flow becomes turbulent, and the thickness of the... Dust particles of diameter 0.06 mm and density 1.6 g/cm 3 are unsettled during high winds and rise to a height of 200 m by the time things calm down. Estimate how long it takes for the dust particles... Consider a 2-m-high electric hot-water heater that has a diameter of 40 cm and maintains the hot water at 55°C. The tank is located in a small room whose average temperature is 27°C, and the... Consider an airplane whose takeoff speed is 220 km/h and that takes 15 s to take off at sea level. For an airport at an elevation of 1600 m (such as Denver), determine (a) The takeoff speed, (b) The... A 10-in-thick, 30-ft-long, and 10-ft-high wall is to be constructed using 9-in-long solid bricks (k = 0.40 Btu/h·ft·°F) of cross section 7 in à 7 in, or identical size bricks... The cylindrical chimney of a factory has an external diameter of 1.1 m and is 20 m high. Determine the bending moment at the base of the chimney when winds at 110 km/h are blowing across it. Take the... Define thermal conductivity and explain its significance in heat transfer. Consider heat loss through the two walls of a house on a winter night. The walls are identical, except that one of them has a tightly fit glass window. Through which wall will the house lose more... Consider laminar flow of air across a hot circular cylinder. At what point on the cylinder will the heat transfer be highest? What would your answer be if the flow were turbulent? Consider a hot boiled egg in a spacecraft that is filled with air at atmospheric pressure and temperature at all times. Will the egg cool faster or slower when the spacecraft is in space instead of... The roof of a house consists of a 15-cm-thick concrete slab (k = 2 W/m·K) that is 15 m wide and 20 m long. The convection heat transfer coefficients on the inner and outer surfaces of the roof... In which mode of heat transfer is the convection heat transfer coefficient usually higher, natural convection or forced convection? Why? A 0.5-m-long thin vertical plate is subjected to uniform heat flux on one side, while the other side is exposed to cool air at 5°C. The plate surface has an emissivity of 0.73, and its midpoint... A 50-m-long section of a steam pipe whose outer diameter is 10 cm passes through an open space at 15°C. The average temperature of the outer surface of the pipe is measured to be 150°C. If... A thin metal plate is insulated on the back and exposed to solar radiation on the front surface. The exposed surface of the plate has an absorptivity of 0.7 for solar radiation. If solar radiation is... Air at 20°C with a convection heat transfer coefficient of 25 W/m 2 ·K blows over a horizontal steel hot plate (k = 43 W/m·K). The surface area of the plate is 0.38 m 2 with a... What is a reradiating surface? What simplifications does a reradiating surface offer in the radiation analysis? The boiling temperature of nitrogen at atmospheric pressure at sea level (1 atm) is - 196°C. Therefore, nitrogen is commonly used in low-temperature scientific studies since the temperature of... How can you determine the view factor F 12 when the view factor F 21 and the surface areas are available? A furnace that has a 40-cm 40-cm glass window can be considered to be a blackbody at 1200 K. If the transmissivity of the glass is 0.7 for radiation at wavelengths less than 3 m and zero for... Under what conditions can the overall heat transfer coefficient of a heat exchanger be determined from U = (1/h i + 1/h o ) -1 ? A long thin-walled double-pipe heat exchanger with tube and shell diameters of 1.0 cm and 2.5 cm, respectively, is used to condense refrigerant-134a by water at 20C. The refrigerant flows through the... Water at an average temperature of 180F and an average velocity of 4 ft/s flows through a thin-walled 3/4-indiameter tube. The water is cooled by air that flows across the tube with a velocity of 12... The top surface of the passenger car of a train moving at a velocity of 70 km/h is 2.8 m wide and 8 m long. The top surface is absorbing solar radiation at a rate of 200 W/m 2 , and the temperature... Warm air is blown over the inner surface of an automobile windshield to defrost ice accumulated on the outer surface of the windshield. Consider an automobile windshield (k w = 0.8 Btu/hftR) with an... An array of power transistors, dissipating 6 W of power each, are to be cooled by mounting them on a 25-cm à 25-cm-square aluminum plate and blowing air at 35°C over the plate with a fan... Water at an average temperature of 110C and an average velocity of 3.5 m/s flows through a 5-m-long stainless steel tube (k = 14.2 W/mK) in a boiler. The inner and outer diameters of the tube are D i... During a winter day, wind at 55 km/h, 5°C, and 1 atm is blowing parallel to a 4-m-high and 10-m-long wall of a house. Approximating the wall surfaces as smooth, determine the friction drag acting... The weight of a thin flat plate 50 cm à 50 cm in size is balanced by a counterweight that has a mass of 2 kg, as shown in Fig. P1554. Now a fan is turned on, and air at 1 atm and 25°C... Two concentric spheres with diameters of 5 cm and 10 cm are having the surface temperatures maintained at 200°C and 100°C, respectively. The enclosure between the two concentric spherical... A solar collector consists of a horizontal copper tube of outer diameter 5 cm enclosed in a concentric thin glass tube of 9 cm diameter. Water is heated as it flows through the tube, and the annular... What is the heat capacity rate? What can you say about the temperature changes of the hot and cold fluids in a heat exchanger if both fluids have the same capacity rate? What does a heat capacity of... Under what conditions will the temperature rise of the cold fluid in a heat exchanger be equal to the temperature drop of the hot fluid? In the heat transfer relation Q = UA s T lm for a heat exchanger, what is T lm called? How is it calculated for a parallel-flow and counter-flow heat exchanger? Using its definition and the values listed in Table A15, determine the volume expression coefficient of saturated liquid water at 70°C. Compare the result with the value tabulated in Table A15.... Can the outlet temperature of the cold fluid in a heat exchanger be higher than the outlet temperature of the hot fluid in a parallel-flow heat exchanger? How about in a counter-flow heat exchanger?... Explain how the LMTD method can be used to determine the heat transfer surface area of a multipass shelland-tube heat exchanger when all the necessary information, including the outlet temperatures,... In the heat transfer relation Q = UA s FT lm for a heat exchanger, what is the quantity F called? What does it represent? Can F be greater than one?
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