Vector Mechanics for Engineers: Statics, 11th Edition
11th Edition
ISBN: 9780077687304
Author: Ferdinand P. Beer, E. Russell Johnston Jr., David Mazurek
Publisher: McGraw-Hill Education
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Chapter 2.5, Problem 2.105P
To determine
Find the weight (W) of the crate.
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Air at 25°C (cp=1006 J/kg.K) is to be heated to 58°C by hot oil at 80°C (cp = 2150 J/kg.K) in a cross-flow heat exchanger
with air mixed and oil unmixed. The product of heat transfer surface area and the overall heat transfer coefficient is 750
W/K and the mass flow rate of air is twice that of oil.
NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.
Air
Oil
80°C
Determine the effectiveness of the heat exchanger.
In an industrial facility, a counter-flow double-pipe heat exchanger uses superheated steam at a temperature of 155°C to
heat feed water at 30°C. The superheated steam experiences a temperature drop of 70°C as it exits the heat exchanger.
The water to be heated flows through the heat exchanger tube of negligible thickness at a constant rate of 3.47 kg/s. The
convective heat transfer coefficient on the superheated steam and water side is 850 W/m²K and 1250 W/m²K,
respectively. To account for the fouling due to chemical impurities that might be present in the feed water, assume
a fouling factor of 0.00015 m²-K/W for the water side.
The specific heat of water is determined at an average temperature of (30 +70)°C/2 = 50°C and is taken to be
J/kg.K.
Cp=
4181
Water
Steam
What would be the required heat exchanger area in case of parallel-flow arrangement?
The required heat exchanger area in case of parallel-flow arrangement is
1m².
A single-pass crossflow heat exchanger is used to cool jacket water (cp = 1.0 Btu/lbm.°F) of a diesel engine from 190°F to 140°F, using
air (Cp = 0.245 Btu/lbm.°F) at inlet temperature of 90°F. Both air flow and water flow are unmixed. If the water and air mass flow rates
are 85500 lbm/h and 400,000 lbm/h, respectively, determine the log mean temperature difference for this heat exchanger. Assume
the correction factor F to be 0.92.
Air flow
(unmixed)
Water flow
(unmixed)
The log mean temperature difference of the heat exchanger is
°F.
Chapter 2 Solutions
Vector Mechanics for Engineers: Statics, 11th Edition
Ch. 2.1 - Two forces are applied as shown to a hook....Ch. 2.1 - Two forces are applied as shown to a bracket...Ch. 2.1 - Prob. 2.3PCh. 2.1 - Prob. 2.4PCh. 2.1 - A stake is being pulled out of the ground by means...Ch. 2.1 - A telephone cable is clamped at A to the pole AB....Ch. 2.1 - A telephone cable is clamped at A to the pole AB....Ch. 2.1 - A disabled automobile is pulled by means of two...Ch. 2.1 - A disabled automobile is pulled by means of two...Ch. 2.1 - Two forces are applied as shown to a hook support....
Ch. 2.1 - A steel tank is to be positioned in an excavation....Ch. 2.1 - A steel tank is to be positioned in an excavation....Ch. 2.1 - A steel tank is to be positioned in an excavation....Ch. 2.1 - For the hook support of Prob. 2.10, determine by...Ch. 2.1 - Prob. 2.15PCh. 2.1 - Solve Prob. 2.1 by trigonometry.Ch. 2.1 - Solve Prob. 2.4 by trigonometry.Ch. 2.1 - For the stake of Prob. 2.5, knowing that the...Ch. 2.1 - Prob. 2.19PCh. 2.1 - Prob. 2.20PCh. 2.2 - Determine the x and y components of each of the...Ch. 2.2 - Determine the x and y components of each of die...Ch. 2.2 - Prob. 2.23PCh. 2.2 - 2.23 and 2.24 Determine the x and y components of...Ch. 2.2 - Member BC exerts on member AC a force P directed...Ch. 2.2 - Member BD exerts on member ABC a force P directed...Ch. 2.2 - The hydraulic cylinder BC exerts cm member AB a...Ch. 2.2 - Cable AC exerts on beam AD a force P directed...Ch. 2.2 - The hydraulic cylinder BD exerts on member ABC a...Ch. 2.2 - The guy wire BD exerts on the telephone pole AC a...Ch. 2.2 - Determine the resultant of the three forces of...Ch. 2.2 - Determine the resultant of the three forces of...Ch. 2.2 - Determine the resultant of the three forces of...Ch. 2.2 - Determine the resultant of the three forces of...Ch. 2.2 - Knowing that = 35, determine the resultant of the...Ch. 2.2 - Prob. 2.36PCh. 2.2 - Knowing that = 40, determine the resultant of the...Ch. 2.2 - Knowing that = 75, determine the resultant of the...Ch. 2.2 - Prob. 2.39PCh. 2.2 - Prob. 2.40PCh. 2.2 - PROBLEM 2.41 Determine (a) the required tension in...Ch. 2.2 - PROBLEM 2.42 For the block of Problems 2.37 and...Ch. 2.3 - Two cables are tied together at C and loaded as...Ch. 2.3 - Two forces of magnitude TA = 8 kips and TB = 15...Ch. 2.3 - The 60-lb collar A can slide on a frictionless...Ch. 2.3 - A chairlift has been stopped in the position...Ch. 2.3 - Two cables are tied together at C and are loaded...Ch. 2.3 - Two cables are tied together at C and are loaded...Ch. 2.3 - Prob. 2.45PCh. 2.3 - Two cables are tied together at C and are loaded...Ch. 2.3 - 2.47 Two cables are tied together at C and are...Ch. 2.3 - Knowing that = 20, determine the tension (a) in...Ch. 2.3 - Two cables are tied together at C and are loaded...Ch. 2.3 - Two cables are tied together at C and are loaded...Ch. 2.3 - Prob. 2.51PCh. 2.3 - 2.52 Two forces P and Q are applied as shown to an...Ch. 2.3 - A welded connection is in equilibrium under the...Ch. 2.3 - A welded connection is in equilibrium under the...Ch. 2.3 - A sailor is being rescued using a boatswains chair...Ch. 2.3 - A sailor is being rescued using a boatswains chair...Ch. 2.3 - For the cables of Prob. 2.44, find the value of ...Ch. 2.3 - For the cables of Prob. 2.46, it is known that the...Ch. 2.3 - For the situation described in Fig. P2.48,...Ch. 2.3 - 2.60 Two cables tied together at C are loaded as...Ch. 2.3 - A movable bin and its contents have a combined...Ch. 2.3 - Free-Body Diagram...Ch. 2.3 - Collar A is connected as shown to a 50-lb load and...Ch. 2.3 - Collar A is connected as shown to a 50-lb load and...Ch. 2.3 - 2.65 Three forces are applied to a bracket as...Ch. 2.3 - A 200-kg crate is to be supported by the...Ch. 2.3 - A 600-lb crate is supported by several...Ch. 2.3 - Solve parts b and d of Prob. 2.67, assuming that...Ch. 2.3 - A load Q is applied to the pulley C, which can...Ch. 2.3 - An 1800-N load Q is applied to pulley C, which can...Ch. 2.4 - Prob. 2.71PCh. 2.4 - Prob. 2.72PCh. 2.4 - A gun is aimed at a point A located 35 east of...Ch. 2.4 - Solve Prob. 2.73 assuming that point A is located...Ch. 2.4 - Prob. 2.75PCh. 2.4 - Prob. 2.76PCh. 2.4 - Cable AB is 65 ft long, and the tension in that...Ch. 2.4 - PROBLEM 2.78 Cable AC is 70 ft long, and the...Ch. 2.4 - Prob. 2.79PCh. 2.4 - Prob. 2.80PCh. 2.4 - 2.81 A force acts at the origin of a coordinate...Ch. 2.4 - A force acts at the origin of a coordinate system...Ch. 2.4 - A force F of magnitude 210 N acts at the origin of...Ch. 2.4 - Prob. 2.84PCh. 2.4 - 2.85 A frame ABC is supported in part by cable DBE...Ch. 2.4 - Prob. 2.86PCh. 2.4 - In order to move a wrecked truck, two cables are...Ch. 2.4 - In order to move a wrecked truck, two cables are...Ch. 2.4 - A rectangular plate is supported by three cables...Ch. 2.4 - A rectangular plate is supported by three cables...Ch. 2.4 - Find the magnitude and direction of the resultant...Ch. 2.4 - Find the magnitude and direction of the resultant...Ch. 2.4 - Knowing that the tension is 425 lb in cable AB and...Ch. 2.4 - Knowing that the tension is 510 lb in cable AB and...Ch. 2.4 - Prob. 2.95PCh. 2.4 - For the plate of Prob. 2.89; determine the...Ch. 2.4 - The boom OA carries a load P and is supported by...Ch. 2.4 - Prob. 2.98PCh. 2.5 - Three cables are used to tether a balloon as...Ch. 2.5 - A container of mass m = 120 kg is supported by...Ch. 2.5 - A 150-lb cylinder is supported by two cables AC...Ch. 2.5 - A transmission tower is held by three guy wires...Ch. 2.5 - A container is supported by three cables that are...Ch. 2.5 - A container is supported by three cables that are...Ch. 2.5 - Three cables are used to tether a balloon as...Ch. 2.5 - Three cables are used to tether a balloon as...Ch. 2.5 - Prob. 2.103PCh. 2.5 - Prob. 2.104PCh. 2.5 - Prob. 2.105PCh. 2.5 - Prob. 2.106PCh. 2.5 - Three cables are connected at A, where the forces...Ch. 2.5 - Fig. P2.107 and P2.108 2.108 Three cables are...Ch. 2.5 - A rectangular plate is supported by three cables...Ch. 2.5 - A rectangular plate is supported by three cables...Ch. 2.5 - A transmission tower is held by three guy wires...Ch. 2.5 - A transmission tower is held by three guy wires...Ch. 2.5 - In trying to move across a slippery icy surface, a...Ch. 2.5 - Fig. P2.113 2.114 Solve Prob. 2.113 assuming that...Ch. 2.5 - For the rectangular plate of Probs. 2.109 and...Ch. 2.5 - PROBLEM 2.116 For the cable system of Problems...Ch. 2.5 - PROBLEM 2.117 For the cable system of Problems...Ch. 2.5 - Prob. 2.118PCh. 2.5 - Prob. 2.119PCh. 2.5 - Three wires are connected at point D, which is...Ch. 2.5 - A container of weight W is suspended from ring A,...Ch. 2.5 - Knowing that the tension in cable AC of the system...Ch. 2.5 - Prob. 2.123PCh. 2.5 - Prob. 2.124PCh. 2.5 - Fig. P2.113 2.114 Solve Prob. 2.113 assuming that...Ch. 2.5 - Prob. 2.126PCh. 2 - Prob. 2.127RPCh. 2 - Prob. 2.128RPCh. 2 - A hoist trolley is subjected to the three forces...Ch. 2 - Knowing that = 55 and that boom AC exerts on pin...Ch. 2 - Two cables are tied together at C and loaded as...Ch. 2 - Two cables tied together at C are loaded as shown....Ch. 2 - The end of the coaxial cable AE is attached to the...Ch. 2 - Knowing that the tension in cable AC is 2130 N,...Ch. 2 - Find the magnitude and direction of the resultant...Ch. 2 - Prob. 2.136RPCh. 2 - Collars A and B are connected by a 25-in.-lang...Ch. 2 - Fig. P2.137 and P2.138 2.138 Collars A and B are...
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- using the theorem of three moments, find all the reactions and supports, I need concise calculations only. the answers are at the bottom, I need concise steps and minimal explanationsarrow_forwardIn an industrial facility, a counter-flow double-pipe heat exchanger uses superheated steam at a temperature of 155°C to heat feed water at 30°C. The superheated steam experiences a temperature drop of 70°C as it exits the heat exchanger. The water to be heated flows through the heat exchanger tube of negligible thickness at a constant rate of 3.47 kg/s. The convective heat transfer coefficient on the superheated steam and water side is 850 W/m²K and 1250 W/m²K, respectively. To account for the fouling due to chemical impurities that might be present in the feed water, assume a fouling factor of 0.00015 m² K/W for the water side. The specific heat of water is determined at an average temperature of (30+70)°C/2 = 50°C and is taken to be Cp J/kg-K. Water Steam Determine the heat exchanger area required to maintain the exit temperature of the water to a minimum of 70°C. The heat exchanger area required isarrow_forwardStress, ksi 160 72 150- 140 80 70 ༄ ྃ ༈ ཎྜ རྦ ༅ ཎྜ ྣཧྨ ➢ 130 120 110 100 90 2.0 2.8 3.6 4.4 5 Wire diameter, mm 6.0 6.8 2 7.6 8.4 Compression and extension springs. ASTM A227 Class II Light service Average service 0.020 0.060 0.100 0.140 0.180 0.220 0.260 0.300 0.340 0.380 0.420 0.460 0.500 Wire diameter, in Torsional stress due to initial tension, ksi 10 ४ 20 Preferred range 100 Stress, MPa 9.2 10.0 10.8 11.6 12.4 1100 1035 965 895 825 760 Severe service 690 620 550 50 150 3456789 10 11 12 13 14 15 16 Spring index, C = DJD FIGURE 18-21 Recommended torsional shear stress in an extension spring due to initial tension (Data from Associated Spring, Barnes Group, Inc.) 50 200 485 Stress, MPaarrow_forward
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