Originally Posted by

**kevinnwhat** Hi all, ive ran into a problem with this question, it reads,

calculate the work against gravity required to build the structure out of brick using the method of examples 2 and 3. Assume that brick has density 80lb/ft^3

A tower of height 20ft and square base of side 10ft.

I tried to figure out the work on one small layer, than take the integral from 0 to 20. So i first calculated the volume of each layer which i got 100*delta y, than i got the mass which is 8000, than i calculated the work (9.8)(8000)*delta y i than got F = 78400 delta y. So i tried to integrate that from 0 to 20 but i keep getting the wrong answer, anyone help me out here?