Sep 28, 2015  I was thinking about making a magnet charger and this was an experiment to see if the idea was any good. Now I've proved to myself that the theory is possible I will buy a stronger pair of. When the button is subsequently released, the capacitor is discharged through the core winding. That causes a very strong magnetic field to flow in a loop through the core's cross-piece, one of the magneto's pole pieces, the magneto's magnet, the other pole piece and back to the cross-piece.

After trying out our simple demonstration of magnetohydrodynamic (MHD) propulsion, you might want to make something a little more “practical.” Here’s how to build a simple little boat that moves through salt water (at a snail’s pace) via MHD propulsion.

The craft is not designed for performance; it’s designed to demonstrate a functional MHD craft made with inexpensive, easily available materials. While it may move slowly, hey, it moves, and you can make it in about five minutes.
[This is the second in a series of three articles on building simple magnetohydrodynamic (MHD) propulsion systems.]

Materials, clockwise from noon:

• 9V batteries. Plural, because they will get used up very quickly. Rechargables would be nice.
• Two quarters (or similar coins)
• Two short cables with alligator clips on the ends
• A sturdy foamtray, like the kind that meat or vegetables are sometimes packed in
• a strong neodymium magnet (I suggest one about an inch in diameter
  by half an inch thick)
• Regular transparent tape.Tools: a small knife.Optional: Double-sided tape.Since your vehicle requires salt water to run, you will also need to provide that. Grab some salt, water, and a nonmagneticbasin that’s at least several times as wide as your craft. A plastic storage bin or kiddie pool works well. If your bathtub is nonmagnetic (check it!) you can use that. While the craft could (in principle) run in the ocean, wind and water currents will make it hard to see the small propulsion effect.

  First step: Wrap the outside of your magnet with a single layer of tape to electrically insulate it. Electrical tape, packing tape, or other types of insulating tape will also work for this job.In the photo, you can see that my half-inch thick “magnet” is actually a stack of two 1/4″ thick magnets.

  Step 2: Using more tape, attach the magnet to the tray. You can see in the first photo where the magnet will end up: towards one end of the tray and centered in the other direction.If you have double-sided tape, use a piece below the magnet to help hold it in place.

  Make the incisions. Use a knife to score a short, narrow slit along two sides of the magnet as shown. The slits should be allow you to push the two quarters into the foam tray where they are held in place by friction. It’s a good idea to make the initial slits narrow and short (shorter than a quarter) so that the quarters will be held in place securely and the seal will be water tight. The quarters should be parallel, centered around the magnet, and as close to the magnet as possible.Danger: You must exercise extreme caution when handling a sharp knife near a strong magnet like this. The safe way to cut these slits is to first mark where the magnet goes, take the magnet off, cut the slits, and thentape the magnet on.

  Carefully attach the 9V battery to the craft, it should happily stick to the magnet.Begin wiring up the craft: Hook one end of each of the two alligator cables to the battery terminals. (Don’t hook the terminals to each other.)If you don’t already have any alligator clip cables, this is a great excuse to make or buy some.

  To complete your MHD boat, clip the other ends of the two alligator cables to the two quarters. Go get the Dom, it’s time for the maiden voyage.When you float the craft in salt water, the water completes the electric circuit, allowing electricity to flow between the two exposed half-quarters on the bottom side of the tray. As in the case of the simple MHD demonstration, the electric current flows perpendicularly to the magnetic field, so a force is produced, which will push the craft along.

  Avoid getting salt water in the top of the tray; it will short out the circuit and drain your battery without giving you any propulsion.

  Get your basin ready and salt the water.We used this clear storage bin to test out our little boat. The water is a couple of inches deep, so that the quarters won’t touch bottom. We emptied that container of salt into it, but I’m not convinced that we needed quite that much.

  Because we’re using such a small battery, the total thrust is not very high. To see it, you will need to avoid other factors that can move the boat. Most importantly, you need to avoid water currents, wind currents, and nearby magnets or ferromagnetic items.

  We had an early shipwreck with this design when we tried to test it out in our bathtub. It turns out that our bathtub is magnetic. The boat was almost instantly yanked to the bottom. Oops. A more subtle problem is that your craft may slowly float towards the nearest giant chunk of steel, so don’t try this right next to your car. Once you eliminate major magnetic interference, you may find that your craft still acts as a weak compass. (If your magnet pointed horizontally instead of vertically, it would make a
  very good compass.)

  The compass effect will only mess with your steering, not the thrust direction. If you’re careful, you should then be able to tell compass steering from attraction towards metal objects.

  To check for magnetic interference without eating up batteries, disconnect one of the alligator clips from the battery and set the craft in the basin of water. If it starts drifting (not turning), then you need to put your basin somewhere else. Once you’ve found an interference-free test site, reconnect your battery.

  To test your MHD craft, place it in the center of your salt water basin. Assuming that you’ve removed magnetic interference, the craft will begin to move forward. However, without knowing which pole of your magnet is which, you can’t tell which way forward will be. The end with the magnet is either the bow or the stern. If you’d like it to go the other way, swap the role of the two alligator clips at the battery end.

  To prolong battery life, always take the craft out of the water as soon as it hits one of the walls. Disconnect the battery if it’s going to spend any significant time sitting out before the next run.

  Short movie (43 s, no sound), demonstrating this magnetohydrodynamic propulsion craft on YouTube.

  Troubleshooting

  If you have trouble getting your craft to work, the first suspect should be the battery; try a new one. There’s very little to go wrong in this circuit, so it should (in principle) be easy to debug. If the battery is hot and the craft doesn’t move, then you may have a short circuit. Check to make sure that you don’t have any water leaks (remember that salt water is a conductor!) and make sure that the insulating wrap around your magnet is intact.

  What’s next?

  This might be a good starting point for a larger vehicle, as a classroom
  demonstration, or a science fair project. That’s up to you. Right now, I’m making radio controlled versions. How will it turn out? Time will tell!

CKEditor 5 Builds are a set of ready-to-use rich text editors. Every “build” provides a single type of editor with a set of features and a default configuration. They provide convenient solutions that can be installed with no effort and that satisfy the most common editing use cases.

# Available builds

The following CKEditor 5 Builds are currently available:

# Classic editor

Classic editor is what most users traditionally learnt to associate with a rich text editor — a toolbar with an editing area placed in a specific position on the page, usually as a part of a form that you use to submit some content to the server.

During its initialization the editor hides the used editable element on the page and renders “instead” of it. This is why it is usually used to replace <textarea> elements.

In CKEditor 5 the concept of the “boxed” editor was reinvented:

• The toolbar is now always visible when the user scrolls the page down.
• The editor content is now placed inline in the page (without the surrounding <iframe> element) — it is now much easier to style it.
• By default the editor now grows automatically with the content.

To try it out online, check the classic editor example. Jump to Quick start to start using it.

# Inline editor

Inline editor comes with a floating toolbar that becomes visible when the editor is focused (e.g. by clicking it). Unlike classic editor, inline editor does not render instead of the given element, it simply makes it editable. As a consequence the styles of the edited content will be exactly the same before and after the editor is created.

A common scenario for using inline editor is offering users the possibility to edit content in its real location on a web page instead of doing it in a separate administration section.

To try it out online, check the inline editor example. Jump to Quick start to start using it.

# Balloon editor

Balloon editor is very similar to inline editor. The difference between them is that the toolbar appears in a balloon next to the selection (when the selection is not empty):

To try it out online, check the balloon editor example. Jump to Quick start to start using it.

# Balloon block editor

Balloon block is essentially the balloon editor with an extra block toolbar which can be accessed using the button attached to the editable content area and following the selection in the document. The toolbar gives an access to additional, block–level editing features.

To try it out online, check the balloon block editor example. Jump to Quick start to start using it.

# Document editor

The document editor is focused on rich text editing experience similar to the native word processors. It works best for creating documents which are usually later printed or exported to PDF files.

To try it out online, check the document editor example. Jump to Quick start to start using it.

# Build customization

Every build comes with a default set of features and their default configuration. Although the builds try to fit many use cases, they may still need to be adjusted in some integrations. The following modifications are possible:

• You can override the default configuration of features (e.g. define different image styles or heading levels).
• You can change the default toolbar configuration (e.g. remove undo/redo buttons).
• You can also remove features (plugins).

Read more in the Configuration guide.

If a build does not provide all the necessary features or you want to create a highly optimized build of the editor which will contain only the features that you require, you need to customize the build or create a brand new one. Check Custom builds for details on how to change the default builds to match your preferences.

# Additional information

# How builds were designed

Each build was designed to satisfy as many use cases as possible. They differ in their UI, UX and features, and are based on the following approach:

• Include the set of features proposed by the Editor Recommendations project.
• Include features that contribute to creating quality content.
• Provide setups as generic as possible, based on research and community feedback.

# Use cases

Each of the builds fits several different use cases. Just think about any possible use for writing rich text in applications.

The following are some common use cases:

• In content management systems:
  • Forms for writing articles or website content.
  • Inline writing in a frontend-like editing page.
  • Comments.
• In marketing and sales automation applications:
  • Composing email campaigns.
  • Creating templates.
• In forum applications:
  • Creating topics and their replies.
• In team collaboration applications:
  • Creating shared documents.
• Other uses:
  • User profile editing pages.
  • Book writing applications.
  • Social messaging and content sharing.
  • Creation of ads in recruitment software.

# When NOT to use builds?

CKEditor 5 Framework should be used, instead of builds, in the following cases:

• When you want to create your own text editor and have full control over its every aspect, from UI to features.
• When the solution proposed by the builds does not fit your specific use case.

In the following cases CKEditor 4 should be used instead: Winning eleven 49 ps2 game.

• When compatibility with old browsers is a requirement.
• If CKEditor 4 contains features that are essential for you, which are not available in CKEditor 5 yet.
• If CKEditor 4 is already in use in your application and you are still not ready to replace it with CKEditor 5.

In the following cases Letters may be used instead:

• When you want an easy way to enable, as part of your application, the creation of articles and documents that feature:
  • Real-time collaborative writing.
  • Inline comments and discussion in the content.
  • Advanced writing features.