Here's why:

* Buoyant force: This is an upward force exerted by a fluid (liquid or gas) on an object submerged in it. It's essentially the result of the pressure difference between the top and bottom of the object.

* Gravity: This is a downward force that pulls all objects towards the center of the Earth.

When an object is submerged in a fluid, the buoyant force acts upwards, trying to push the object up. Gravity acts downwards, trying to pull the object down. The interaction of these two forces determines the object's fate:

* Object floats: If the buoyant force is greater than the gravitational force, the object floats.

* Object sinks: If the gravitational force is greater than the buoyant force, the object sinks.

* Object is suspended: If the buoyant force and gravitational force are equal, the object remains suspended in the fluid.

Let me know if you'd like to explore any of these concepts in more detail!