Machine-translated by Google. Questions are authored in English.
Top

Discussion

A tank is excavated in a level ground to a depth of 8 m with uniform side slopes. The top of the tank at ground level is rectangular in shape of size 40 × 20 m, while the bottom is of size 24 × 12 m. Compute the volume of earthwork by the trapezoidal rule.

  • A.\(4152\ \text{m}^3\)
  • B.\(4252\ \text{m}^3\)
  • C.\(4312\ \text{m}^3\)
  • D.\(4352\ \text{m}^3\)

Answer: D

The volume of earthwork by the trapezoidal rule is the mean of the end areas times the depth. The top area is \(40 \times 20 = 800\) m\(^2\) and the bottom area is \(24 \times 12 = 288\) m\(^2\):

\[ \begin{aligned} V = \frac{800 + 288}{2} \times 8 = 544 \times 8 \\ &= 4352\ \text{m}^3 \end{aligned} \]

The prismoidal formula would give a slightly smaller value (about 4181 m\(^3\)), and the other options are different from both rules.

No comment is present. Be the first to comment.
Loading…

Post your comment

Please log in or register to post a comment.