This set of Fluid Mechanics Multiple Choice Questions & Answers (MCQs) focuses on “Geometrical Properties of Trapezoidal Section”.
Explanation: Total Wetted Area = 2(Area of triangle) + (Area of rectangle)
A = 2(1⁄2 Zy)(y) + (By)
A = Zy2 + By
A = y(Zy + B).
3. What is the top width of a trapezoidal channel having depth y, side slope Z and base B?
Explanation: Top Width = Base+2Zy
T = B+2Zy.
4. Calculate the hydraulic depth of a trapezoidal channel section having depth 4m, base of 5m and side slope 1H:2V.
5. Calculate the hydraulic radius of a trapezoidal section having depth 5m, side slope 1H:3V and base of 6m.
6. Calculate the section factor of a trapezoidal channel section having depth 8m, base 5m and side slope 1H:2V.
7. Estimate the discharge of water in a trapezoidal channel section having a depth 3m, width of 6m, side slope of 1H:2V and velocity of water is 2m⁄s.
Explanation: Discharge (Q) = AV
A = (B+Zy)y
A = (6+1/2 (3))(3)= 22.5m2
Q = (22.5)(2)
Q = 45m3⁄s.
8. Calculate the side slope of a trapezoidal channel section having base 8m, depth 4m and the hydraulic radius is 2.36m.
9. Calculate the top width of a trapezoidal channel section having a side slope1H:4V, base of 5m and the wetted area is 17.25m2.
10. The product Zy in a Trapezoidal channel is 2 and the side slope is1/2. Calculate the wetted perimeter of the channel section if the wetted is 32m2.
A = (B+Zy)y;B=6m
Wetted Perimeter = B+2y√(1+Z2)
P = 14.94m.
11. The top width of a trapezoidal channel is 12m, the bottom width of the channel is 6m and the side slope is 1H:2V, calculate the wetted perimeter.
Explanation: Top Width = B+2Zy
12 = 6 +2(1/2)(y); y=6m
P = B+2y√(1+Z2)
P = 19.41m.
12. The wetted area of a trapezoidal section is 15m^2 and the top width is 6m, calculate the section factor.
13. The ratio of section factor and hydraulic depth in a trapezoidal section is 324/25, calculate the top width if the total wetted area of the channel is 24m2.
Explanation: Ratio = (section factor)/(hydraulic depth) = 324/25
324/25 =√A √T; √T=49
T = 7m.
Sanfoundry Global Education & Learning Series – Fluid Mechanics.
To practice all areas of Fluid Mechanics, here is complete set of 1000+ Multiple Choice Questions and Answers.