Question

the wall of a dam is broad at its base

Answer 1

As we move further down under water, the pressure increases. The walls of dams are broader at the base in order to bear the high pressure at the bottom of water.

Answer 2

ANSWER:

The wall of the dam is 'broad at its base' because the force exerted by the liquid in 'increases with increase in depth'.

EXPLANATION:

The wall constructed in broad and strong at base so that the huge volume of water equally occupy the space available and also it is not exerting much pressure on the walls to avoid the damage. In this way the sinking of water is avoided in water.