The Physics in Swimming Physics is defined as the branch of science concerning the study of matter and energy and the interactions between the two. Physics tries to explain the nature of the world around us, how things happen and why. Swimming displays some physical properties, such as buoyancy, drag resistance and propulsion. We swimmers are at a constant battle to stay afloat, while fighting through the water and propelling ourselves forward, and we do so using technique.
Buoyancy is the power to float or rise in a fluid. This relates to swimming because when you’re in the water, you have to be able stay afloat. Buoyancy is the net upward force acting on the swimmer, as the depth of the water increases, so does the pressure. The pressure bellow the swimmer is greater than the pressure above it, which is how swimmers float. When you’re at the surface, there is less resistance since water is more resistant than air. So the goal for the swimmer is to stay as close to the surface as possible to be more buoyant.
The higher up the swimmer is in the water, the less water they have to swim wrought, causing the swimmer to displace less water, to practically swim on top of the water. To establish this buoyancy, swimmers use technique. Because your upper body has a greater surface area than your lower body, it’s much easier for you upper body to float. So the goal is to keep the lower body streamlined, and to push your chest down so your hips can rise. When it comes to combating drag, swimmers have three main types of drag acting on them: friction, wave and pressure drag.
Frictional drag comes from the interaction between the swimmer’s body and the water, which lows down the swimmer. But if you look at Newton’s third law, for every action there’s an equal and opposite reaction, this frictional drag is not only slowing the swimmer down, it is also propelling the swimmer through the water. As the swimmer gets faster, pressure drag starts kicking in. As a swimmer gets faster, there is an increase of pressure acting on the front region of the body, specifically the head. This increase in pressure causes a difference between the two ends of the body and results in turbulence.
The third form of drag, wave drag, happens when a swimmer r any object moves through the surface of a liquid. Due to the different water velocities, the pressure around the swimmer’s body increases, resulting in waves. These waves can cause problems. The amplitude of the waves increase as the swimmer gets faster, causing more resistance. To reduce drag, swimmers use the streamline position when they are first pushing through the water, such as when they first dive in, or when they do a flippant off of the walls to start a new lap. It reduces the amount of surface area the front part of the body is covering.
The quenching used in the arms when swimming is also another way they fight drag. They extended their arm far to try to make their body as long as possible, to diminish wave drag. Swimmers also have specialized suits and caps to help decrease drag. In swimming, to propel yourself in the water, you use a combination of your arms and legs. Swimmers perfect techniques to maximize the amount of propulsion going on, such as the extension of the arms, the kick, etc. Water is 773 times denser than air, which means the amount of force exerted by the swimmer has to be greater to move lull/kick to truly be fast in their swimming.
