Question

A dam has broader walls at the bottom than at the top. Explain.

Answer 1

The pressure exerted by a liquid increases with its depth. Thus as depth increases, more and more pressure is exerted by water on wall of the dam. A thicker wall is required to withstand greater pressure, therefore, the thickness of the wall of dam increases towards the bottom.

Answer 2

A dam has broader walls at the bottom than at the top because the pressure exerted by liquid increases with its depth, and at any point at a particular depth liquid pressure is the same in all directions. Now as more pressure is exerted by water on the wall of the dam as depth increases. Hence a thick wall is constructed at the bottom of the dam to withstand greater pressure.