# Teaching Students About Water Resistance

Water resistance is a force that uses friction to slow things down that are moving through water. It is often called drag.

Water resistance doesn’t have to be just water. However, it can happen to objects moving through any fluid. Water resistance happens because of the particles in water or the liquid. As the thing moves through, it collides with the particles, which try to slow it down.

Several factors affect this force:

• Different-shaped objects have different levels of water resistance; streamlined shapes have less and can move through water much more quickly. If an object is turned sideways, it will likely be easier to push it through the water. It is why fish are shaped the way they are. The area is one of the most significant factors affecting water resistance. An object larger will collide more with water particles and therefore have a more substantial drag force. If you spread your body by jumping into the water, you will encounter more water resistance.
• Velocity can affect this force too. An object with a more significant velocity will have a more potent drag force; this is how fast the thing initially travels through the water. The faster it is going, the stronger the drag force.
• The texture of the object is another common factor affecting the force.
• The density of the fluid it is moving through can also affect it. Density is how much matter is packed into a substance and how tightly packed the particles are. The dense the water, the greater the drag force.

Forces

As water resistance is a type of force, it is a good idea to establish what a force is so your class understands the effects of drag.

A force can push or pull objects and change their shape, speed, or direction.

A force meter, otherwise known as a Newton meter, is used to measure the force of an object in Newton (N). This meter has a spring inside, stretched out; the stretch’s size determines the force’s size.

Examples of using Water Resistance

A similar force to water resistance is air resistance, a type of friction between the air and another object, like an airplane. The air particles hit the aircraft, making it harder to move through the air.

Water resistance is the same as this but with objects moving through the water. For example, if you go swimming, you must push the water out of the way to move forward because there is friction between your skin and the water particles.

Science of Swimming – The level of water resistance increases if your body is completely submerged in the water, making it harder to move. Therefore, swimmers tend to go towards the surface as much as possible because moving through air resistance allows a better movement speed than water resistance.

Penguins and Water Resistance – the Penguins, can glide through the water with little water resistance because they are slim and have bullet-shaped bodies. However, their feathers do slow them down. To change their direction, they can stick out their flippers which steer them against the water.