# Disk with holes falling on water

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• epenguin

#### epenguin

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TL;DR Summary
Anyone seen a video about it?
Just yesterday evening I saw a video of a few minutes where metal disks with holes in them were let fall into a basin of water.The water went up in twisted columns and made the most astounding and beautiful patterns. I thought I would show it to other people who might be interested - but I have forgotten where I saw it! I thought it was on this site, but I can't find it. The only other possible place would have been by chance on YouTube.

Has anybody seen it, by any chance?

I saw it just recently. That kind of stuff comes up on my Facebook feed regularly.
Can't remember what the group was called.
Google combinations of 'slow motion water drop disc' videos.

epenguin said:
Has anybody seen it, by any chance?
Try this:

That's exactly the one, thank you @Ibix and @BilTre !

Last edited:
Ibix

## 1. How does a disk with holes falling on water create a vortex?

As the disk falls, it pushes the water out of the way and creates a depression in the water's surface. This depression causes the water to flow towards the center of the disk, creating a vortex.

## 2. What factors affect the size and shape of the vortex created by a disk with holes falling on water?

The size and shape of the vortex can be affected by the size and shape of the holes in the disk, the speed at which the disk falls, and the viscosity of the water.

## 3. Can the direction of the vortex be controlled by changing the orientation of the disk?

Yes, the direction of the vortex can be controlled by changing the orientation of the disk. If the disk is dropped with the holes facing downwards, the vortex will rotate clockwise. If the holes are facing upwards, the vortex will rotate counterclockwise.

## 4. Is there a limit to the size of the vortex that can be created by a disk with holes falling on water?

The size of the vortex depends on the size and speed of the disk, as well as the properties of the water. However, there is a limit to how large the vortex can become. Once the disk reaches a certain speed, the vortex will break apart into smaller vortices.

## 5. What real-world applications can be derived from studying the phenomenon of a disk with holes falling on water?

Studying this phenomenon can help us understand the dynamics of fluid flow and how vortices are created. This knowledge can have practical applications in fields such as engineering, meteorology, and oceanography. It can also be used to improve the design of products such as propellers and turbines that utilize the principles of fluid dynamics.