Here's why:
* Density: Density is a measure of how much mass is packed into a given volume. Steel is a very dense material.
* Buoyancy: Objects float if they are less dense than the fluid they are in. Water has a density of 1 gram per cubic centimeter.
* Steel's density: Steel has a density of around 7.85 grams per cubic centimeter, which is significantly greater than water's density.
Therefore, since steel nails are denser than water, they sink.