EF 152 Exam 1 Fall 2018 Page 1 Copy 165 Name: Seat Assignment: Specify your EXAM ID on the right. Use 000 if you don t know your exam ID. Circle your TEAM SECTION 11:10 12:40 2:10 216 217 218 A216 Matt B216 Matt C216 Matt A217 Cole B217 Cole C217 Cole A218 Landon 0 0 0 1 1 1 2 2 2 3 3 3 4 4 4 5 5 5 6 6 6 7 7 7 8 8 8 9 9 9 Instructions Do not open the exam until instructed to do so. Do not leave if there is less than 5 minutes to go in the exam. When time is called, immediately stop writing, remain seated, and pass your exam to the center aisle. Working after time is called results in an automatic deduction. Turn your equation sheets in with your exam. Guidelines Assume 3 significant figures for all given numbers unless otherwise stated Show all of your work no work, no credit Write your final answer in the box provided Include units for all answers
EF 152 Exam 1 Fall 2018 Page 2 Copy 165 1. (2 pt) A gauge pressure is reported as 42 psi. What is the corresponding absolute pressure? (P atm = 14.7 psi = 101300 Pa) 42 psi 0 psi 56.7 psi 27.3 psi 2. (2 pt) A 2 cm 3 marble weighing 5 grams sinks when dropped in water. Which is true about the specific gravity (SG) of the marble? 0 < SG 0.5 0.5 < SG 1 1 < SG 3. (2 pt) Water flows through a horizontal pipe that doubles in diameter as shown. Ignoring losses, how does velocity v 2 compare to velocity v 1? fluid 1 d 2d 2 v 2 = 4 v 1 v 2 = 2 v 1 v 2 = v 1 v 2 = ½ v 1 v 2 = ¼ v 1 4. (2 pt) Water flows through a horizontal pipe that doubles in diameter as shown. Ignoring losses, how does pressure p 2 compare to pressure p 1? fluid 1 d 2d 2 p 2 > p 1 p 2 < p 1 p 2 = p 1 Not enough info 5. (2 pt) A pitot tube is submerged in an open channel stream. The immersed end is 6 cm below the surface of the stream. The water in the pitot tube rises 13 cm above the surface of the stream. What is the speed of the stream? v = sqrt(2*9.81 m/s 2 *0.06 m) v = sqrt(2*9.81 m/s 2 *0.13 m) v = sqrt(2*9.81 m/s 2 *0.19 m)
EF 152 Exam 1 Fall 2018 Page 3 Copy 165 6. (2 pt) A Poise is a unit of velocity viscosity energy volume flow rate 7. (2 pt) A house in a hurricane zone has a roof area of 700 sq ft. Determine which equation to use to determine the required wind speed to lift off the roof if the roof weighs 14000 lb. Assume the roof is not tied down. v = sqrt(2gh) (p1 p2) = 0.5 air v 2 L = air K A v 2 8. (4 pt) What is the period of Jupiter if its mean orbital distance to the sun is 5.2 times larger than Earth s mean orbital distance? 2.28 yrs 3.00 yrs 5.2 years 11.86 years 9. (4 pt) A 40 m x 30 m shark tank has an underwater circular viewing window with a diameter of 4m. The center of the window is 3 m below the surface of the tank. What is the average gauge pressure on the window? 29.4 kpa 123 kpa 370 kpa 616 kpa 35300 kpa 10. (4 pt) A hose with a cross sectional area of 2.50 x 10-4 m 2 is used to fill a tank with a volume of 8.00 x 10-3 m 3 in 30 seconds. Find the speed of the water that leaves the hose. 0.667 m/s 1.07 m/s 32 m/s 960 m/s
EF 152 Exam 1 Fall 2018 Page 4 Copy 165 11. (6 pts) What is the mass density of the static fluid in the Manometer shown? 0.6 m 12. (6 pts) Determine the angular velocity of a 50 kg satellite orbiting earth at a fixed altitude of 15000 km. G=6.6742 x 10-11 N-m 2 /kg 2, m earth=5.97 x 10 24 kg, r earth=6380 km 13. (6 pts) A steel column of length 120 inches and a cross-sectional area of 14.6 in 2 undergoes a strain of 472x10-6 due to an axial load. What is the factor of safety if its compressive (axial load) strength is 50,000 lb/in 2? (Elastic Modulus Steel = 29 x 10 6 lb/in 2 )
EF 152 Exam 1 Fall 2018 Page 5 Copy 165 14. (14 pts) What is the magnitude of the reaction at the pin support? Assume the frame weight is negligible. A free body diagram is required for full credit.
EF 152 Exam 1 Fall 2018 Page 6 Copy 165 15. (14 pts) Coach Pruitt s weight is 985 Newtons. His weight suspended underwater (spring scale force) is 54 Newtons. What is his average mass density? A free body diagram is required for full credit.
EF 152 Exam 1 Fall 2018 Page 7 Copy 165 16. (14 pts) A 12-inch long compound tube consists of an outer steel tube bonded to an inner brass tube with areas as shown. Find the amount the tube shortens when subject to an axial load of 207 pounds. A s = 8.6 in 2 E s = 29x10 6 lb/in 2 A b = 7.1 in 2 E b = 14x10 6 lb/in 2 12 in Continued on back of this page
EF 152 Exam 1 Fall 2018 Page 8 Copy 165 17. (14 pts) Water flows steadily from a tank open to the atmosphere as shown in the figure. The cross-sectional area at point 2 is 0.048 m 2 and the cross sectional area at point 3 where the water is discharged to the atmosphere is 0.039 m 2. The cross-sectional area of the tank is very large compared with the cross-sectional area of the pipes. Find the gauge pressure at point 2. Assume no losses.