One of the earliest forms of transportation to be developed was marine or water
transportation. The first boats were probably made out of logs either lashed together to
form rafts or dug out logs to form primitive boats. As technology improved new boats
and forms of power were discovered. The science of mechanics and fluids (how boats
move) is called hydrodynamics. This science has made it possible for ships to carry
larger cargos, travel farther, and travel faster then ever before.
A boat’s ability to float is called buoyancy. As a boat is on the water it creates a
force that pushes down because of gravity. Water also creates a force that pushes up on
the boat. If the force of the water pushing up on the boat is greater then the force of the
boat pushing down, then the boat will float.
In order for a boat to transport cargo, it also needs to be able to remain stable in the
water. Stability is the ability of a boat to remain upright in the water. If the boat does
not stay upright in the water, then the cargo on the boat will fall off. Hulls are designed
to keep a boat floating and upright. There are two main types of hulls. Flat/Planing
hulls are used to transport cargo in shallow waters and ride higher on the surface of the
water. Displacement hulls include rounded hulls or v-shaped hulls. These hulls displace
the water allowing the boat to float and ride lower in the water.