Question

Why is the bottom part of the foundation of a building made wider?

Answer 1

Hint: As we all can see in our surroundings that any of the huge building’s bottom part is wider. If the bottom part is not wide, then the base of the building is not so strong and it can sink down on the ground.

Formula used:
The pressure is given as:
$P = \dfrac{F}{A}$
where, $P$ is the pressure, $F$ is the force exerted on the area, and $A$ is the cross-sectional area.

Complete answer:
Buildings are large structures that put a lot of pressure on the earth and are prone to sinking, so their foundations are made wide to reduce the pressure on the ground. Foundation of a building is made wider so that it may not sink under the extremely high pressure of the building. The broad foundation distributes the weight of the building over the ground.

The area of the surface is inversely proportional to the pressure. The foundation of the building should have a larger area in order for the building to exert less strain on the ground and not sink into it. In other words, high-rise constructions are large structures that put a lot of pressure on the ground and are prone to sinking.

As a result, their foundations are designed wide to reduce the pressure on the earth and avoid sinking. As we know, the same force acting on a smaller area exerts a bigger pressure, whereas the same force acting on a larger area imposes a smaller pressure.

Note: Dams have a wider foundation. The reason for this is that the pressure imposed by a liquid increases as the depth of the liquid increases. Because a bigger wall is necessary to withstand higher pressure, the dam's thickness grows as it approaches the bottom.