Engineering Answers

22. What are the shortcomings of grillage analysis which is commonly used in structural analysis of bridges?

What is the consideration in selecting the orientation of wing walls in the design of bridge abutments?

The indicating liquid in the manometer shown in the figure below is water and benzene with a density of 880 kg/m³. These two liquids are essentially insoluble in each other. If the two liquids are essentially insoluble in each other. If the manometer reading is ΔZ = 37.19 cm of water, what is the pressure difference P₁ - P₂ in kN/m². Show detailed calculations.

A mixture containing 10% ethanol (E) and 90% H₂O (W) by weight is fed into a distillation column at the rate of 106.26 kg/h. The distillate (top product) contains 94.01 % ethanol and the distillate is produced at a rate of one tenth of that of the feed. 

_{Draw and label a flow chart of the process before solving the problem. Perform material (total) and ethanol balances to calculate the mass fraction of ethanol in the bottom product to at least four decimal places.} 

12. A new temperature scale in o E is proposed wherein the boiling and freezing temperatures of water are

1250 o E and 85 o E respectively. If a fluid system has a temperature of 525 o E, determine its temperature

in a) o C and b) o R.

11. A Fahrenheit and a Celsius thermometer are both immersed in a fluid. a) If the two numerical readings

are identical, what is the temperature of the fluid expressed in o K and o R. b) If the Fahrenheit

temperature is numerically twice that of the Celsius reading, what is the temperature of the fluid

expressed in o K and o R?

10. If a pump discharges 90 GPM of water whose specific weight is 61.5 lb f /ft 3 (g = 31.95 ft/s 2 ), find a) mass

flow rate (lb m /min), b) time to fill a spherical tank 8 ft in diameter.

8. A vertical composite fluid column whose upper end is open to the atmosphere is composed of 20

inches of mercury (S.G = 13.45), 30 inches of water (density = 62.4 lb m /ft 3 ) and 35 inches of oil (S.G =

0.825). Determine the absolute pressure in psia: a) at the base of the column, b) at the oil-water

interface, c) at the water-mercury interface.

6. A tank is in the form of a right circular cylinder with hemispherical ends. The overall length of the tank is

4 meters and the diameter of the hemisphere is 1 meter. If a pump discharges a fluid whose density is

1.2 kg m /Liter in this tank at a rate of225 liters per minute determine a.) Weight of liquid inside the tank if

it is half full. b) total time to fill the tank assuming it is initially empty.

5. A pilot notices that the barometric pressure outside his aircraft is 85 kPaa. The airport below the plane

reports a barometric pressure of 100 kPaa. If the average air density is 1.15 kg m /m 3 and the local gravity

is 9.75 m/s 2 , determine the height of the aircraft above the ground in meters.