Zamboanga Peninsula Polytechnic State University
COLLEGE OF ENGINEERING AND TECHNOLOGY
Civil Engineering Department
MIDTERM EXAMINATION SET A
CED 314 – HYDRAULICS
Name: ______________________________________________________________ Date: _______________________________________________________________
Section: ____________________________________________________________ Score: ______________________________________________________________
I. PROPERTIES OF FLUIDS: (10 Points) 6. The factor of safety against sliding must not be less than 1.2 and
Instruction: Solve the following problems and SHOW YOUR the factor of safety against overturning must not be less than 1.8.
SOLUTIONS. Determine the safe value of "b" of the dam section shown neglecting
hydrostatic uplift. The specific weight of concrete is 23.60 kN/m 3
1. Determine the true pressure in Pa at the center of a vessel if the and the coefficient of friction between base and the foundation soil
2.25mm diameter piezometer in inserted into the wall of the vessel is 0.55. (5 pts)
at the level of the center and
a. Oil ( so =0.84 , σ o=0.0 655 N /m ¿stands 294mm with wetting
angle of 30 ° . (2 pts)
b. Mercury ( shg =1 3.6 , σ hg=0. 493 N /m) stand 405mm. (2 pts)
c. Water (σ w =0. 0868 N /m) stands 345mm. (2 pts)
7. A rectangular tank if internal width of 5 m as shown in the figure,
contain soil of sp. gr = 0.8 and water.
a. Find the depth of oil, h. (2 pts)
b. Find the volume displaced by the block if a 1000 N block of wood
2. Calculate the dynamic and kinematic is floated in the oil. (2 pts)
viscosity of an oil which is used for c. Find the rise in free surface of the water in contact with air? (2
lubrication between a square plate of pts)
size 0.8m x 0.8m and an inclined plane
with an angle of inclination 30 ° as shown.
The mass of the square plate is 300N and
it slides down the inclined plane with a
velocity of 0.3meter per second. The
thickness and specific gravity of the oil
film is 1.5mm and 0.95, respectively. (4
II. PRINCIPLE OF HYDROSTATIC: (6 Points) IV. RELATIVE EQUILIBRIUM OF LIQUIDS: (21 Points)
Instruction: Solve the following problems and SHOW YOUR Instruction: Solve the following problems and SHOW YOUR
SOLUTIONS. SOLUTIONS.
3. Determine the weight W if a force F=350N is applied as shown for 8. An unbalanced vertical force of 270 N upward accelerates
the case where: a volume of 0.075 m^3 of water. If the water is 0.9 m deep in a
a. The bottom surface of the weight is at the same level as the center cylindrical tank.
of the piston. (2 pts) a. What is the acceleration of the tank? (2 pts)
b. The bottom surface of the weight is 3.25 m above the center of b. What is the pressure at the bottom of the tank in N/m2? (2 pts)
the piston. (2 pts) c. What is the force acting on the bottom of the tank in N? (3 pts)
c. The bottom surface of the weight is 0.9 m below the center of the
piston. (2 pts)
III. TOTAL HYDROSTATIC FORCE ON SURFACES: (23 Points) 9. An open tank 3 m by 3 m in horizontal section weighs 3.6 kN and
Instruction: Solve the following problems and SHOW YOUR contains water to a depth of 1 m. It is acted by an unbalanced force
SOLUTIONS. of 16 kN parallel to a pair of sides. (6 pts)
a. Determine the acceleration of the tank.
4. A cylindrical tank 4 m. in diameter and 9 m. high contains liquids b. Determine the height of the tank so that no water will spill out.
A, B and C with equal heights. Specific gravity of A, B and C are 1.5, c. If the acceleration is increased by 4 m/s2, how much water will be
2.4 and 3.5 respectively. The tank is provided by steel hoops at the spilled out?
bottom and at the top. (6 pts)
a. Compute the total hydrostatic force acting on the wall of the tank. 10. A closed cylindrical vessel 1.0 m diameter and 2.0 m high
b. Compute the tension of hoops at the bottom of the tank. contains water 1.5 m deep, the remaining air space being under a
c. Compute the tension of hoops at the top of the tank. pressure of 120 kPa. (8 pts)
a. Compute the pressure at the center of the bottom if ω = 12 rad/s.
5. If the center of gravity of a ship in the upright position is 12m b. Compute the pressure at the circumference of the bottom.
above the center gravity of the portion under water, the c. What ω will just zero the depth of water at the center.
displacement being 1,000 metric tons, and the ship is tipped 42
degrees causing the center of buoyancy to shift by 10m.
a) Find the location of the metacenter from the bottom of the ship if
its draft is 4.5m. (2 pts)
b) Find the metacentric height (2 pts)
Good
c) What is the value of the righting moment in kg-m. (2 pts)
