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| Forms of Water |
 Title text: The 'light' refers to bremsstrahlung. |
Explanation
This comic plays on the idea that the heavy water suggests the existence of "light water" via nucleon reduction. Since heavy water has a hydrogen atom that contains two nucleons and regular water has a hydrogen atom that contains one nucleon, an extrapolation could be made to conclude that a new water variant exists called light water, which has a "hydrogen" atom that doesn't contain any nucleons at all. A hydrogen isotope of two nucleons is a deuterium, while a hydrogen isotope of one nucleon is called a protium. A "hydrogen" atom of zero nucleons would be identical to an ium, a fictional isotope as shown in 2719: Hydrogen Isotopes.
"Light water", as depicted in this comic, is fictional, as a hydrogen isotope of zero nucleons cannot exist. This is due to the fact that an atom's element type is dependent on the amount of protons; a hydrogen atom is, by definition, an atom containing one proton, and all atoms, again by definition, have to contain at least one proton.
A hydrogen atom has an associated electron, balancing the positive charge on its proton. The "light water" depicts the electron present, meaning it would just be a hydroxide ion (if there's still one atom of regular hydrogen), or oxide ion (if both hydrogen atoms are "light").
The title text clarifies that "light" refers to bremsstrahlung. Bremsstrahlung is electromagnetic radiation in the form of high-energy photons produced when a charged particle slows down; this particle is usually an electron. This is therefore a wordplay on "light" (not heavy) and light (photons), as well as referencing the presence of the electron particle in "light water".
Although not depicted in the comic, deuterium-depleted water is sometimes known as light water. The term light-water reactor also shares a similar name.
Transcript
- [Three diagrams of molecules are shown, each with an associated diagram. Each molecule features a large circle labeled O, representing an oxygen atom, with one smaller circle on each side labeled H, representing hydrogen atoms. Each molecule has an arrow pointing to the right-hand hydrogen atom, with the arrow starting near a diagram. Each diagram has a label below it.]
- [Diagram of an atom, with one black dot representing an electron in orbit around a nucleus consisting of one white circle representing a proton and one gray circle representing a neutron.]
- Heavy water
- [A similar diagram, with one black dot representing an electron in orbit around a nucleus consisting of one white circle representing a proton.]
- Water
- [A similar diagram, with one black dot representing an electron in orbit with no nucleus.]
- Light water
This Week's Explanation for Improvement
As part of the Explanation Improvement Project, each week the community selects one older, stagnant, or otherwise neglected explanation to expand and polish together. This week's pick is comic 976: Sail, you can help us by editing its explanation!
To get involved with the project, you can also nominate an explanation that you think should be improved, or vote on current nominations!
| Sail |
 Title text: It only works a few times before you have to capsize the boat in a soap lagoon again. |
Explanation
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Welcome to This Week's Explanation for Improvement! Anyone is encouraged to help explain comic 976: Sail; click here to get started! If you are new to wiki editing, you can read our editing FAQ for guidance. Here are some suggestions for improving this explanation: .svg){kind=icon} Explain whether this idea could actually work in real life, (with the right weather conditions)
.svg){kind=icon} How fast would the wind need to be to form a bubble?
.svg){kind=icon} What is Cueball pulling? Is he trying to create the bubble or govern the ship?
.svg){kind=icon} Would a boat be able to float in a "soap lagoon"?
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A billowing sail sometimes looks like the first stage of blowing a bubble. A strong gust of wind blows by and fills the sail, which Cueball is clearly surprised by and fights to keep the sail under control. As the wind continues, the sail warps and begins acting like a film of bubble soap, eventually separating into its own bubble and floating off and the sail reverting to the original position, as the gust of wind dies down. Sails do not typically act like this under strong winds[citation needed].
If the booms and mast were actually attached by a rope on the far side, the sail frame could function as a large bubble wand. Commercial 'bubble ropes' can have an area of at least a couple of square metres, but it would need the right velocity and consistency of wind to sustain the bubble long enough to separate cleanly from the sail. This could, theoretically, be possible under extreme wind conditions, but it would be rare to find such winds.
The title text suggests that the water the boat is sailing in is a soap solution that can be used to create the bubbles. If the boat was overturned (capsized) in such water, a film would form between the mast and the boom. The film would become like the sail in the comic, filling with air and forming bubbles. However, with each bubble that is released the remaining film on the boat would become thinner, until it can no longer sustain itself, at which point it would need to be refilled by capsizing again. While this arrangement could be used to produce large bubbles with a sufficient film, Cueball would likely not have to pull on the mainsheet as much as is depicted in the comic, as the 'sail' isn't mechanically attached to the vessel for long, since it is a bubble film, not a piece of cloth.
Transcript
- [Cueball is sailing a lateen rigged sailboat.]
- [The wind picks up, pushing the sail forward.]
- [The wind builds strength. Cueball has to stand up to hold on to the main sheet, with shaking depicting his tugging.]
- [The distorted sail balloons out. Cueball is still holding on to the main sheet. More curves depict a stronger tugging.]
- [Part of the sail separates into a bubble. Cueball falls backwards into the boat. The sail begins to return to its normal shape.]
- [Cueball lands on his rear and scratches his head in confusion as the sail-sized bubble floats away.]
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