Problem: Article: In quantum mechanics, the quantum of action is the Planck constant, usually denoted as h. Likewise, for interacting subatomic particles, the quantum of angular momentum is the reduced Planck constant (the Planck constant divided by 2) denoted by and called "h-bar". The value of the Planck constant is extremely small, its units are those of angular momentum, and the notion of action is the more general mathematical concept. As the name quantum mechanics implies, certain physical quantities such as angular momentum can change only in discrete amounts, and not in a continuous (cf. analog) way. For example, the angular momentum of an electron bound to an atom or molecule is quantized and can only have values that are multiples of the reduced Planck constant. This quantization gives rise to electron orbitals of a series of integer primary quantum number. In contrast, the angular momentum of a nearby unbound electron is not quantized. The Planck constant also plays a role in the quantum theory of light, where the quantum of light is the photon and where matter and energy interact via the atomic electron transition or "quantum leap" of the bound electron. The units of the Planck constant can also be viewed as energy times time. For example, in the subject area of particle physics, the notion of virtual particles are messy particles that spontaneously appear out of the vacuum for a tiny fraction of a section and play a role in a particle interaction. The limit to the lifetime of these virtual particles is the energy (mass) of the particle times that lifetime. Quantum mechanics is a large subject area but every part of its mathematics involves the Planck constant. Massy particles go through a classical-to-quantum transition. Even though the free electron displays some quantum properties (such as spin), as the unbound electron approaches the atom and slows down (perhaps by emitting photons), it undergoes a transition from classical to quantum behavior as its energy goes below the ionization energy. The electron is then bound to the atom and its angular momentum with respect to the atomic nucleus is restricted to quantized values of the orbitals it can occupy. The transition is sudden. One might compare this transition with that of a mechanical system that changes from displaying unstable to stable behavior or from displaying simple to chaotic behavior, or even a rocket ship slowing and going below escape velocity and entering orbit around some star or other celestial object. In contrast photons (which are massless) do not go through such a transition: photons just travel through space unchanged until they interact with other particles and then disappear. As you look into the night sky, the photons from some star traveled through light years of space unchanged then interacted with an electron in a molecule of your retina, transferred its energy and then otherwise disappeared.
Summary: Start with learning about the physical significance of the Planck constant. Learn about massy particles.

Problem: Article: Sap tends build up into a thick, hard layer if you don't clean it off regularly. If your car tends to pick up a lot of sap, plan to clean it off every other week or so - more often in the summer, when it's more concentrated and will smear more easily. This will keep you from having a tougher job on your hands down the line. You can also apply a sap remover product from your auto supply store, but rubbing alcohol works just as well. Let the towel sit on the sappy area for at least 10 minutes. The alcohol will begin to break down and soften the hard sap. Use a microfiber cloth to rub off the softened sap. If the sap won't budge, you'll need to soak it again for another 10-20 minutes. Keep soaking and rubbing the sap until it's removed from your car's exterior. If the sap is difficult to remove, cover it with WD-40, which should help it loosen up. Don't use WD-40 on your windows, though. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/3\/3e\/Remove-Bugs%2C-Tar%2C-and-Sap-from-Your-Car-Step-8Bullet1.jpg\/v4-459px-Remove-Bugs%2C-Tar%2C-and-Sap-from-Your-Car-Step-8Bullet1.jpg","bigUrl":"\/images\/thumb\/3\/3e\/Remove-Bugs%2C-Tar%2C-and-Sap-from-Your-Car-Step-8Bullet1.jpg\/aid42218-v4-728px-Remove-Bugs%2C-Tar%2C-and-Sap-from-Your-Car-Step-8Bullet1.jpg","smallWidth":460,"smallHeight":306,"bigWidth":"728","bigHeight":"485","licensing":"<div class="mw-parser-output"><p>License: <a rel="nofollow" class="external text" href="https:\/\/en.wikipedia.org\/wiki\/Fair_use">Fair Use<\/a> (screenshot)<br>
<\/p><\/div>"} Don't use a scrubbing sponge or any other rough material to scrub the sap from your car's body, because the paint will likely come off with the sap. If dried sap won't come off your windows, use a box cutter blade to carefully scrape it off. Don't use this method to remove sap from other parts of your car. After the sap has been removed, it's a good idea to wash your car to get rid of any residue. Little bits of leftover sap could dry elsewhere on your car, leaving you to deal with the problem all over again.
Summary: Remove sap every few weeks. Soak a cloth in rubbing alcohol and apply it to the sap on your car. Rub the area to remove the sap. Scrape the toughest sap from your windshield and windows. Wash your car.

Problem: Article: If you're feeling dizzy from your nausea, try not to move around too much, even when your stomach is doing somersaultsunless vomiting is imminent. The most important thing to do when fighting dizziness is to keep your head still. Always get up slowly after resting to prevent head spins. Alternatively, if you get head spins, you can work through it.
Summary: Lie or sit down in a comfortable position.

Problem: Article: Make sure not to lose the bearing ring on the fork that was resting in the lower cup of the frame.
Summary:
Slide the fork down, out of the frame. Slide the bearing ring and O-ring up, off the frame.