How fast is 100 knots underwater? That is a very simple question with a simple answer. But do you know how much 100 knots underwater will be on road? Do you know if there is any creature or device underwater that could achieve 100 knots? By the end of this article, you should get all these questions answered.

If we want to answer all these questions, then there is a need to understand what knot means in the first place.

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## What is a knot?

The knot is not an SI unit but it is a unit of measurement that is used in the measurement of maritime speed and air navigation. This same unit is also used in measurements of windspeed.

The ISO standard mathematical symbol for this unit is ‘kn‘. There are times when ‘kt‘ is also used to represent knots mathematically.

One knot is equal to one nautical mile per hour and that is to say, 1 knot is equal to 1.852 kilometres per hour.

It is believed that the knot unit of measurement originated from sailors. During those times, sailors will tie multiple precise knots on a rope, and use it together with a sand glass to navigate the waters. It is believed that the knot unit of measurement originated from this act.

## How Fast Is 100 Knots Underwater?

If something is moving at 100 knots it means the thing is moving really fast. It means the object should be moving at a speed of 115.2 miles per hour. This might not sound like anything new since sports cars could go more than twice that speed.

You must consider that this speed is underwater and water is way heavier than air. 100 knots is almost impossible to achieve underwater.

The swordfish is believed to be the fastest-living creature in the sea. It can hit a top speed of 59.02 knots making it faster than every creature in the sea.

The fastest submarine as believed by most people is a Soviet Union submarine known as the K-222. This submarine can hit up to 44.7 knots. You might think this is just 51.44 miles per hour and so it is too slow but it is not. That is because underwater movement is difficult compared to that when on land.

## FAQ

How fast is 100 knots in a plane?

100 knots in a plane means the plane is moving at a speed of 115.2 miles per hour. Planes can easily achieve that speed but submarines can not because of the density of water compared to air.

Why do ships use knots instead of miles per hour?

There are many reasons why ships use knots instead of miles per hour or kilometres per hour.
1. The knots are directly tied to the general latitude and longitude coordinate system.
2. Speed of winds, storms, etc are measured in knots and these are factors sailors must consider when moving vessels.
3. It is easier to measure with knots on the water since there are no fixed roads on the water.

How many knots is the fastest ship?

HSC Francisco is believed to be the fastest passenger vessel on earth right now. Hitting up to 58 knots (67 mph), it is definitely the fastest passenger ship.
It has been on this record since 2012 when it was launched and no other passenger vessel has broken this record yet.