Question

A dam has broader walls at the bottom than at the top . Give a reason

Answer 1

........so to withstand high lateral force which is more as we go deeper in water

Answer 2

Pressure exerted by a liquid is dependent on the depth that it increases with greater pressure . That is to say, as the depth increases, pressure applied by water on the walls of the dam also increases. In order to withstand the great pressure, the walls are build thicker. Hence a dam has broader walls at the bottom then at the top.

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