The face of a dam is shaped like an isosceles trapezoid with a lower base of 44 meters, an upper base of 108 meters, and a height of 114 meters. Find the force on the face of the dam when the water level is 35 meters below the top of the dam.

Explanation:

Given:

length of upper base of trapezoid,

length of lower base of trapezoid,

height of the trapezoid,

water level from the top of the dam,

The depth of water from the base of the dam wall:

Now the pressure on the dam wall due to water upto the given level:

Now refer the schematic for the area on which the water pressure acts.

Now we have the area as:

Now the force on the dam wall can be given as:

6 cos 34, 6 sin 34 trig