Do Fat People Float?

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Many people assume that fat people do not float in water, as their weight makes them sink to the bottom. However, this is not usually true.

In fact, studies have shown that obese people are more likely to float in water, especially when compared to other people who are considered fit and healthy.

But why is this the case? Well, it has something to do with density. Despite the negative connotations now associated with fat, the substance itself is actually less dense than water, which means it will float when placed in liquid.

A good example of this is when you add oil to water, which results in the oil rising to the surface.

In contrast, muscle is denser than water and so it sinks. However, the physics of why fat people float is not that simple. So let’s take a closer look at how this works and what it means for bigger bodies.

Why Do Fat People Float?

The physics behind floating in water is a lot more complex than just weight. Instead, floating comes down to components such as density and displacement.

Understanding Density

To understand why fat people float, we must first take a look at density and how it can impact the ability to float in water.

Density is a term used to describe the mass per unit volume for a particular substance or matter. In simple terms, this means how tightly packed something is.

It is also possible to use density as a way to measure the weight of something compared to its overall size.

For example, imagine that you have two balls of the same size. One ball is hollow and made from plastic, while the other ball is solid and made from lead.

Without question, you already know that the plastic ball will float in water, while the lead ball will sink to the bottom. Despite being of the same size, it is the density of the balls that makes up the difference.

While we can imagine the density of a solid material, it is important to remember that liquids such as water also come with their own density too.

This means that when an object is less dense than water, it will float, while objects denser than water will sink.

To describe the density relationship between two different substances, it is common to use the term specific gravity, which describes the ratio with a single numerical value.

In terms of water, the density can change depending on temperature, although many people agree that it has a specific gravity of 1.0.

Because of this, anything with a specific gravity denser than 1.0 will sink in water. While anything that is less than 1.0 will float.

Fat vs Muscle – Which is Denser?

But what does all this have to do with fat people floating? Well, by understanding the density of fat, muscle and water – we can learn more about why fat people float and why other people don’t.

In most cases, fat has a density of 0.901g/cm3, while muscle has a density of around 1.1g/cm3 – this means that fat is less dense than water, which makes it naturally buoyant when placed in liquid. In contrast to this, muscle is denser than water and so it will sink when submerged.

This helps to explain why people with muscle tissue sometimes weigh more than they look, as muscle is dense and therefore heavier than fat. This also means that it is heavy in the water and that it will most likely sink.

Other Tissues & Buoyancy

Of course, human beings are made up of more than just fat and muscle, they are also composed of bones, organs and a wide range of other tissues, which all come with their own density.

While these values can vary depending on age and nutrition, it is common for bones to have a density of 1.39g/cm3, which means they will sink when placed in water.

On the other hand, blood has a density almost equal to water, which means the substance could either float or sink.

It is also important to remember that 60% of the human body is made up of water, which also helps humans to float.

We know that density is also a significant factor when it comes to floating in water, even though elements such as buoyancy and displacement should also be considered.

For example, when a person gets into a bathtub, it is common for the water to spill out because there is not enough room for both the water and the person.

This is called displacement, and it happens whenever a person enters a body of water. However, it just happens to be more noticeable in a bathtub.

But that’s not the end of it. When you enter the bath and displace water, you will also experience an upward force.

This force is called buoyancy, and it plays an important role in the physics of floating.

In most cases, fat people will displace more water, while also creating a greater buoyancy that allows them to float.

Can Fat People Float In Cold Water?

Of course, they can! In fact, everyone floats better in cold water because it is denser than warm or room temperature water.

As we previously mentioned, floating is all about the relationship between the density of the object and the density of the water.

This means that by lowering the temperature of the water, you can increase its density, which makes it easier for fat people (and everyone else) to float.

Salt Water vs Fresh Water – Best For Floating?

While it may be hard to imagine, saltwater is actually denser than freshwater and is, therefore, easier to float in – regardless of whether you are fat or not.

For example, if your body composition is average, or you have some muscle, then you might find that you sink in freshwater but float better in the sea.

This is because salt water has an average density of around 1.02g/cm3 – 1.03g/cm3 – which makes it a little denser than normal water.

However, this value is not universal, as there are many cases of salt water having a greater density. For example, the Dead Sea is famous for its floating capabilities and currently boasts a density of 1.24g/cm3.

In fact, the Dead Sea is so dense that even a bowling bowl can float in its waters – so there should be no problems for a human being to float.

Final Thoughts

Do fat people float? Yes – in fact, they float better than people who boast muscular and fit bodies. This is because fat is less dense than water and will therefore float to the surface.

While there are many factors that determine how a person will float, the most important are density, displacement and buoyancy.

Because of this, fat people are perfectly capable of floating in water, although this does not mean that they are naturally good swimmers.

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