What is a Jet Ski and How Does it Work?
Lindsay C.
History of a Jet Ski
It is far from certain when the first Jet Ski appeared. It is certain that there is one and only one man who had the first idea about inventing something that a Jet Ski after many modifications. This man’s name was Clayton Jacobson. Clayton Jacobson II was born in the early 1930’s. In 1955 the Vincent Motorcycle Company came out with the first propeller-driven water scooter. 10 years later, inventor Clayton Jacobson II built the first known stand-up Jet Ski.
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Figure 1 This is one of Jacobson’s stand-up Jet Skis, made in the 1960’s.

Eventually throughout the years, the stand-up Jet Ski morphed into a sit-down craft when he was collaborating with a snow mobile manufacturer. Later on in the process, snow mobile markets were booming and the company Jacobson was working with forgot about the Jet Ski. Jacobson continued to improve his idea, but could not take the ideas to market as long as Bombardier retained the rights. When the company pulled out of the market Jacobson immediately went to Kawasaki. When he met with the company owner, they clicked. In 1972, the Kawasaki Jet Ski© was the first commercially successful PWC in manufacturing history. In 1987, Yamaha came out with its own amazing Waverunner©. As, the years went by Jet Ski marketing went up.

How a Jet Ski Works
There are four main forces that tie into a Jet Ski working.Those forces are; thrust, friction, gravity, and buoyancy. If the thrust is larger than the friction the Jet Ski will move. If the gravity is pulling more than the buoyancy the Jet Ski will sink. It also works vice-versa. Jet Skis are really very simple. A Jet Ski is powered by a motor, which makes the propeller spin, causing it to shoot out water and move forward. A Jet Ski works like an octopus does when in danger. When an octopus is in danger, first it sends out a cloud of black ink to temporally blind its predator. While its predator is struggling through the black ink, the octopus sucks in a gulp of water into its back-side and pushes the water outward, propelling itself forward. This is the same mechanism a Jet Ski uses. Also, a Jet Ski uses potential energy. Potential energy is stored up energy, unlike kinetic energy which is energy of motion. A Jet Ski uses its stored energy (gasoline) and lights that on fire. This causes the propeller to spin and the Jet Ski shoots forward.
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Figure 2 This diagram shows how an octopus moves. It is almost exactly how a Jet Ski moves



Newton’s Third Law
A Jet Ski operates based on Newton’s Third Law. Newton’s third law states that for every action there is an equal and opposite reaction. In other words, if two people put equal amount of force on someone standing in between them, that person in the middle will not move. But, if one of the people on the outside pushes just the slightest bit harder, the person will move because there is not an equal force keeping them balanced. Some more examples are: a book sitting on table will not move because there is no force pushing on the book. But, if a swimmer jumps off a raft, he is propelling himself away from the raft. While at the same time, pushing the raft backwards. For every action there is a reaction and for every push there is a pull.
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Figure 3 As the air pushes down and out of the balloon goes upwards because of the equal and opposite push. This is how a Jet Ski works, but instead of air it uses water to propel itself forward.

A Jet Ski can also be called a Sea Monster or a Sea Doo.
A Jet Ski can go up to 50 miles per hour.
The Jet Ski was explored more than 300 years ago, by Sir Isaac Newton.
A Jet Ski can accommodate up to 3 or 4 people! (But only on certain models)

Force: A push or a pull that, when needed can get things moving.
Mechanism: The way something works; the method of doing something.
Motor: A small and powerful engine used in water vehicles and automobiles.
Propeller: A mechanical device used for boats and aircrafts.

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