The minimum fresh air requirement of a residential building is specified to be 0.35 air change per hour (ASHRAE, Standard 62, 1989). That is, 35 percent of the entire air contained in a residence...
The turbines in steam power plants operate essentially under adiabatic conditions. A plant engineer suggests to end this practice. She proposes to run cooling water through the outer surface of the...
Streams of methane and air (79 mole % N 2 , the balance O 2 ) are combined at the inlet of a combustion furnace pre-heater. The pressures of each stream are measured with open-end mercury manometers,...
Aqueous sulfuric acid solutions containing 15.0 wt% H2SO4 and 80.0 wt% H2SO4 are mixed to form 60.0 wt% product solutions the 15% solution was in a laboratory in which the temperature was 77F. The...
Water is added at varying rates to a 300-liter holding tank. When a valve in a discharge line is opened, water flows out at a rate proportional to the height and hence to the volume V of water in the...
Determine the mass moment of inertia of the thin plate about an axis perpendicular to the page and passing through point O. The material has a mass per unit area of 20kg/m2. 200 mm 200 mm 200 mm
In a multiprogramming and time-sharing environment, several users share the system simultaneously. This situation can result in various security problems. a. What are two such problems? b. Can we...
The gears are subjected to the couple moments shown. Determine the magnitude and coordinate direction angles of the resultant couple moment. Given: M1 = 40 lb⋅ ft M2 = 30 lb⋅ ft θ1 =...
A gear-reduction unit uses the countershaft depicted in the figure. Find the two bearing reactions. The bearings are to be angular-contact ball bearings, having a desired life of 40 kh when used at...
A salt-gradient solar pond is a shallow body of water that consists of three distinct fluid layers and is used to collect solar energy. The upper- and lower-most layers are well mixed and serve to...
A 64-mm-diameter circular follower B is held against cam A as shown. Knowing that the cam exerts on the follower a force of magnitude 80 N directed along the common normal BC, determine the moment of...
A piece of plywood in which several holes are being drilled successively has been secured to a workbench by means of two nails. Knowing that the drill exerts a 12 N m ⋅ couple on the piece of...
Considering the stress concentration at point A in the figure, determine the maximum normal and shear stresses at A if F = 200 lbf. .y 2 in 0 12 in I-in dia. g-in R. 2 in 1-in dia. 15 in 1-in dia.
A rectangular block floats in pure water with 0.5 in, above the surface and 1.5 in below the surface. When placed in an aqueous solution, the block of material floats with 1 in. below the surface....
A split-ring clamp-type shaft collar is shown in the figure. The collar is 2 in OD by 1 in ID by ½ in wide. The screw is designated as ¼ -28 UNF. The relation between the screw...
Three forces act on the ring. Determine the range of values for the magnitude of P so that the magnitude of the resultant force does not exceed F. Force P is always directed to the right. Units Used:...
A thermocouple junction is inserted in a large duct to measure the temperature of hot gases flowing through the duct. (a) If the duct surface temperature Ts is less than the gas temperature T g ,...
The reactive force developed by a jet engine to push an airplane forward is called thrust, and the thrust developed by the engine of a Boeing 777 is about 85,000 lbf. Express this thrust in N and kgf.
Suppose that we have a multiprogrammed computer in which each job has identical characteristics. In one computation period, T, for a job, half the time is spent in I/O and the other half in processor...
A 180-lb man and a 120-lb woman stand side by side at the same end of a 300-lb boat, ready to dive, each with a 16-ft/s velocity relative to the boat. Determine the velocity of the boat after they...
Two sites are being considered for wind power generation. In the first site, the wind blows steadily at 7 m/s for 3000 hours per year, whereas in the second site the wind blows at 10 m/s for 2000...
Pin C is attached to rod BC and slides freely in the slot of rod OA which rotates at the constant rate Ï . At the instant when β = 60°, determine (a) r and θ (b) r...
The pressure gage on a 2.5-m3 oxygen tank reads 500 kPa. Determine the amount of oxygen in the tank if the temperature is 28°C and the atmospheric pressure is 97 kPa. = 500 kPa V- 2.5 m
A natural gas containing 82.0 mole% CH4 and the balance C2H6 is burned with 20% excess air in a boiler furnace. The fuel gas enters the furnace at 298 K, and the air is preheated to 423 K. The heat...
In using the bolt cutter shown, a worker applies two 75-lb forces to the handles. Determine the magnitude of the forces exerted by the cutter on the bolt. 75 05 in. I in. I in. 20 im 4 in. 75 Ib I in.
Consider a concentric tube heat exchanger with an area of 50 m 2 operating under the following conditions: (a) Determine the outlet temperature of the hot fluid (b) Is the heat exchanger operating in...
A rigid tank contains 20 lbm of air at 50 psia and 80F. The air is now heated until its pressure doubles. Determine (a) The volume of the tank and (b) The amount of heat transfer.
Collars B and D are pin-connected to bar ABD and can slide along fixed rods. At the instant shown the angular velocity of bar ABD is zero and the acceleration of point D is 7.2 m/s2 to the right....
(a) Estimate the activation energy for creep (i.e., Qc in Equation 8.20) for the S-590 alloy having the steady-state creep behavior shown in figure. Use data taken at a stress level of 300MPa...
The tensile strength of brittle materials may be determined using a variation of Equation 8.1. Compute the critical crack tip radius for an Al2O3 specimen that experiences tensile fracture at an...
Determine the equivalent resultant force of the distributed loading and its location, measured from point A. Evaluate the integrals using Simpson's rule. Units Used: kN = 103 N Given: c1 = 5 c2 = 16...
You are designing an operating room heat exchange device to cool blood (bypassed from a patient) from 40 to 30C by passing the fluid through a coiled tube sitting in a vat of water-ice mixture. The...
Cite the phases that are present and the phase compositions for the following alloys: (a) 90 wt% Zn-10 wt% Cu at 400(C (750(F) (b) 75 wt% Sn-25 wt% Pb at 175(C (345(F) (c) 55 wt% Ag-45 wt% Cu at...
An uncrowned straight-bevel pinion has 20 teeth, a diametral pitch of 6 teeth/in, and a transmission accuracy number of 6. Both the pinion and gear are made of through-hardened steel with a Brinell...
Determine the magnitude and direction, measured counterclockwise from the positive x' axis, of the resultant force of the three forces acting on the bracket. Given: F1 = 300 N F2 = 200 N F3 = 180 N...
Using superposition, find the deflection of the steel shaft at A in the figure. Find the deflection at midspan. By what percentage do these two values differ?
Determine the moment of inertia of the thin plate about an axis perpendicular to the page and passing through the pin at O. The plate has a hole in its center. Its thickness is c, and the material...
A convergent-divergent nozzle with an exit-to-throat area ratio of 1.616 has exit and reservoir pressures equal to 0.947 and 1.0atm, respectively. Assuming isentropic flow through the nozzle,...
A pistoncylinder device initially contains 0.15-kg steam at 3.5 MPa, superheated by 5°C. Now the steam loses heat to the surroundings and the piston moves down, hitting a set of stops at which...
Refrigerant -134a is being transported at 0.1 kg/s through a Teflon tube of inside diameter D; = 25 mm and outside diameter Do = 28 mm, while atmospheric air at V = 25 m/s and 300 K is in cross flow...
A circular reentrant orifice (also called Borda??s mouthpiece) of diameter D is placed at a depth h below the surface of a tank. Knowing that the speed of the issuing stream is v = ??2gh and assuming...
A gas leak has led to the presence of 1.00 mole% carbon monoxide in a 350-m3 laboratory.4 The leak was discovered and sealed, and the laboratory is to be purged with clean air to a point at which the...
A container of weight W is suspended from ring A, to which cables AC and AE are attached. A force P is applied to the end F of a third cable which passes over a pulley at B and through ring A and...
A model rocket is launched from point A with an initial velocity v0 of 86 m/s. If the rocket??s descent parachute does not deploy and the rocket lands 104 m from A, determine(a) The angle ? that v0...
Flow of a fluid in a network of tubes (Fig. 2B.12), a fluid is flowing in laminar flow from A to B through a network of tubes, as depicted in the figure. Obtain an expression for the mass flow rate w...
At 25 o C, an aqueous solution containing 35.0 wt% H 2 SO 4 has a specific gravity of 1.2563. A quantity of the 35% solution is needed that contains 195.5 kg of H 2 SO 4 . (a) Calculate the required...
Solve Problem 4.96 assuming that for gear A the tangential and radial forces are acting at E, so that FA = (1325 N)j + (482 N)k. P4.96 Gears A and B are attached to a shaft supported by bearings at C...
A biological fluid moves at a flow rate of m = 0.02 kg/s through a coiled, thin-walled, 5-mm-diameter tube submerged in a large water bath maintained at 50C. The fluid enters the tube at 25C. (a)...
Determine the relative amounts (in terms of volume fractions) of the phases for the alloys and temperatures given in Problem 9.8a, b, and c. Below are given the approximate densities of the various...
Consider proportional-only control of the stirred-tank heater control system in Figure. The temperature transmitter has a span of 50F and a zero of 55 F. The nominal design conditions are T = 80 F...
A steel rotating-beam test specimen has an ultimate strength of 150 kpsi and a yield strength of 135 kpsi. It is desired to test low-cycle fatigue at approximately 500 cycles. Check if this is...
The unit cell for tin has tetragonal symmetry, with a and b lattice parameters of 0.583 and 0.318 nm, respectively. If its density, atomic weight, and atomic radius are 7.30 g/cm 3 , 118.69 g/mol,...
A stream containing 7,000 kmol/h of water and 3,000 parts per million (ppm) by weight of ammonia at 350 K and 1 bar is to be processed to remove 90% of the ammonia. What type of separation operation...
A pin in a knuckle joint carrying a tensile load F deflects somewhat on account of this loading, making the distribution of reaction and load as shown in part b of the figure. The usual designers...
A gaseous fuel with 80 percent CH4, 15 percent N2, and 5 percent O2 (on a mole basis) is burned with dry air that enters the combustion chamber at 25°C and 100 kPa. The volumetric analysis of the...
A motorist starts from rest at point A on a circular entrance ramp when t = 0, increases the speed of her automobile at a constant rate and enters the highway at point B. Knowing that her speed...
Liquid water is fed to a boiler at 24C and 10bar and is converted at constant pressure to saturated steam. Use the steam tables to calculate H (kJ/kg) for this process, and then calculate the heat...
A stream of oxygen enters a compressor at 298 K and 1.00 atm at a rate of 127m3/h and is compressed to 358 K and 1000 atm. Estimate the volumetric flow rate of compressed O2 using the...
A solid carbohydrate (C a H b O c ) with a specific gravity of 1.59 is placed in a 1.000-liter combustion chamber. The chamber is evacuated and then charged with pure oxygen. Complete combustion of...
An insulated pistoncylinder device contains 5 L of saturated liquid water at a constant pressure of 150 kPa. An electric resistance heater inside the cylinder is now turned on, and 2200 kJ of energy...
A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -30°C by rejecting its waste heat to cooling water that enters the condenser at...
The force P is applied to a small wheel that rolls on the cable ACB. Knowing that the tension in both parts of the cable is 140 lb, determine the magnitude and direction of P. 30 at 45
The vertical force F acts downward at A on the two membered frame. Determine the magnitudes of the two components of F directed along the axes of AB and AC. Set F = 500N. 30/
Perform the following estimations without using ca calculator. (a) Estimate the mass of water (kg) in an Olympic-size swimming pool. (b) A drinking glass is being filled from a pitcher. Estimate the...
A circular ice rink 25 m in diameter is enclosed by a hemispherical dome 35 m in diameter. If the ice and dome surfaces may be approximated as blackbodies and are at 0 and 15 C, respectively, what is...
Boxes A and B are at rest on a conveyor belt that is initially at rest. The belt is suddenly started in an upward direction so that slipping occurs between the belt and the boxes. Knowing that the...
Consider a system where free space is kept in a free-space list. a. Suppose that the pointer to the free-space list is lost. Can the system reconstruct the free-space list? Explain your answer. b....
Determine the moment of each force acting on the handle of the wrench about the z axis. Given: F1 = (-2 4 -8) lb F2 = (3 2 -6) lb b = 6 in c = 4 in d = 3.5 in θ = 45 deg F
Estimation of void fraction of a packed column, a tube of 146 sq. in. cross section and 73 in. height is packed with spherical particles of diameter 2 mm. When a pressure difference of 158 psi is...
Although KOH, RbOH, and CsOH have little association between metal and hydroxide in aqueous solution, Li+ and Na+ doform complexes with OH-: Na + + OH- NaoH (aq) K1 = 0.20 Prepare a table like the...
An insulated tank is divided into two parts by a partition. One part of the tank contains 2.5 kg of compressed liquid water at 60°C and 600 kPa while the other part is evacuated. The partition is...
A mass of 5 kg of saturated liquidvapor mixture of water is contained in a pistoncylinder device at 125 kPa. Initially, 2 kg of the water is in the liquid phase and the rest is in the vapor phase....
Determine the magnitude and coordinate direction angles of F3 so that the resultant of the three forces is zero. Given: F1 = 180 lb α 1 = 30 deg F2 = 300 lb α 2 = 40 deg F2
In a material processing experiment conducted aboard the space shuttle, a coated niobium sphere of l0-mm diameter is removed from a furnace at 900C and cooled to a temperature of 300C. Although...
Give the approximate minimum temperature at which it is possible to austenitize each of the following ironcarbon alloys during a normalizing heat treatment: (a) 0.20 wt% C, (b) 0.76 wt% C, and (c)...
Copper tubing is joined to the absorber of a flat-plate solar collector as shown. The aluminum alloy (2024- T6) absorber plate is 6 mm thick and well insulated on its bottom. The top surface of the...
The shock waves on a vehicle in supersonic flight cause a component of drag called supersonic wave drag, Dw. Define the wave-drag coefficient as CDw = Dw/q S, where S is a suitable reference area for...
(a) Assume for the solidification of iron (Problem 10.4) that nucleation is homogeneous, and the number of stable nuclei is 106 nuclei per cubic meter. Calculate the critical radius and the number of...
A drug (D) is produced in a three-stage extraction from the leaves of a tropical plant. About 1000 kg of leaf is required to produce 1 kg of the drug. The extraction solvent (S) is a mixture...
A diffuse, gray radiation shield of 60-mm diameter and emissivities of ? 2, i = 0.01 and ? 2, o = 0.1 on the inner and outer surfaces, respectively, is concentric with a long tube transporting a hot...
The small turbine in Fig P6.76 extracts 400 W of power from the water flow. Both pipes are wrought iron. Compute the flow rate Q m3/h. Sketch the EGL and HGL accurately. Water 20 m 20. Turbine 30 m...
A tile-iron consists of a massive plate maintained at 150C by an imbedded electrical heater. The iron is placed in contact with a tile to soften the adhesive, allowing the tile to be easily lifted...
Motion of a sphere in a liquid, a hollow sphere, 5.00 mm in diameter, with a mass of 0.0500 g, is released in a column of liquid and attains a terminal velocity of 0.500 cm/s. The liquid density is...
A 9.780-g gaseous mixture contains ethane (C 2 H 6 ) and propane (C 3 H 8 ). Complete combustion to form carbon dioxide and water requires 1.120 moles of oxygen gas. Calculate the mass percent of...
A mixture of n-heptane (H) and toluene (T) is separated by extractive distillation with phenol (P). Distillation is then used to recover the phenol for recycle as shown in Figure 7.44a, where the...
A uniform slender rod AB rests on a frictionless horizontal surface, and a force P of magnitude 2 N is applied at A in a direction perpendicular to the rod. Knowing that the rod has a mass of 3 kg,...
A mixture of methane and air is capable of being ignited only if the mole percent of methane is between 5% and 15%. A mixture containing 9.0 mole% methane in air flowing at a rate of 700kg/h is to be...
A steam radiator is used to heat a 60-m 3 room. Saturated steam at 3.0bar condenses in the radiator, and emerges as a liquid at the saturation temperature. Heat is lost from the room to the outside...
For an irrotational flow, show that Bernoulli's equation holds between any points in the flow, not just along a streamline.
Determine the largest weight of the oil drum that the floor crane can support without overturning. Also, what are the vertical reactions at the smooth wheels A, B, and C for this case. The floor...
A 1.5-m3 insulated rigid tank contains 2.7 kg of carbon dioxide at 100 kPa. Now paddle-wheel work is done on the system until the pressure in the tank rises to 150 kPa. Determine the entropy change...
Thermal energy storage systems commonly involve a packed bed of solid spheres, through which a hot gas flows if the system is being charged, or a cold gas if it is being discharged. In a charging...
The absolute pressure within a 35.0-liter gas cylinder should not exceed 51.0 atm. Suppose the cylinder contains 50.0 mol of a gas. Use the SRK equation of state to calculate the maximum permissible...
A mixture of propane and butane is burned with air. Partial analysis of the stack gas produces the following dry-basis volume percentages: 0.0527% C 3 H 8 , 0.0527% C 4 H 10 , 1.48% CO. and 7.12% CO...
Calculate the rate of cooling (kW) required to bring 300 kg/mm of carbon monoxide from 450C to 50C, performing the calculation (a) Using Table B.2 and (b) Using Table B.8. Considering how much...
Refrigerant-134a enters the condenser of a residential heat pump at 800 kPa and 55°C at a rate of 0.018 kg/s and leaves at 750 kPa sub cooled by 3°C. The refrigerant enters the compressor at...
Cables AB and AC can sustain a maximum tension Tmax, and the pole can support a maximum compression Pmax. Determine the maximum weight of the lamp that can be supported in the position shown. The...
A cooling coil consists of a bank of aluminum (k = 237 W/m K) finned tubes having the core configuration of figure and an inner diameter of 13.8 mm. The tubes are installed in a plenum whose square...
Determine the force members BC, FC, and FE, and state if the members are in tension or compression. Units Used: kN = 103 N Given: F1 = 6kN F2 = 6kN a = 3 m b = 3 m ET
Ethane gas (C2H6) at 25°C is burned in a steady-flow combustion chamber at a rate of 5 kg/h with the stoichiometric amount of air, which is preheated to 500 K before entering the combustion...