Supercavitating propeller
Okay, so you know how boats have these spinning thingies at the back called propellers that make the boat move? Well, a supercavitating propeller is like a special kind of propeller that can make the boat go even faster!
It does this by making a bubble of air around itself as it spins in the water. This bubble is called a "cavity". The propeller moves so fast that water can't get inside the cavity, so there's just air in there. And since air is lighter than water, the boat can go really, really fast without getting slowed down by the water.
It's kind of like when you ride your bike really fast and stick your hand out the side. If you hold your hand flat, the air pushes against it and it's hard to keep it in one place. But if you hold your hand like a cup, the air goes around it and it's easier to keep your hand steady. The air in the cavity around the supercavitating propeller is kind of like your cupped hand - it helps the boat go faster!
Super cool, right?
It does this by making a bubble of air around itself as it spins in the water. This bubble is called a "cavity". The propeller moves so fast that water can't get inside the cavity, so there's just air in there. And since air is lighter than water, the boat can go really, really fast without getting slowed down by the water.
It's kind of like when you ride your bike really fast and stick your hand out the side. If you hold your hand flat, the air pushes against it and it's hard to keep it in one place. But if you hold your hand like a cup, the air goes around it and it's easier to keep your hand steady. The air in the cavity around the supercavitating propeller is kind of like your cupped hand - it helps the boat go faster!
Super cool, right?
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