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DaveC426913

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DaveC426913 last won the day on August 15 2018

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  1. My favorite was one lady who stuck her first dart in the left scoreboard, and her second dart in the right scoreboard. She was not too pleased that I awarded her the title of having "the widest spread in the club". :)
  2. He is one of the best players in our club. Although that's really not saying much. We just dart for fun, though it is a tournament. At least half our players have trouble hitting the board thrice in a row. He only does occasionally, to keep both skillsets sharp. I'm not sure if he's much worse at underhand than overhand.
  3. Yes. I'd say mentioning playing the film backwards is merely to give an image of : "This is what it would look like, if it happened in reality". Playing the film backwards is not literally part of the concept of thermodynamics they're trying to communicate to the reader.
  4. Not in a closed system. It can increase in an open system (for example, sunlight added to Earth => complex life) But if you extend the boundaries of the system to include the sun, then the overall entropy is actually increasing. Another way to say this is that entropy can temporarily decrease locally in a system, but not globally.
  5. Not related to colours, but there are some non-repeating tesselations (tiles) - arrangements that never repeat on large scales. Pity, I cant seem to find an example. Must be Googling the wrong keywords. [ EDIT ] Ah. "Roger Penrose discovered that it was possible to construct a pattern from just two different shapes, each of them a rhombus with angles which are multiples of 36 degrees; the pattern achieves fivefold symmetry and, most remarkably, can be extended to infinity without repeating itself." https://www.wadham.ox.ac.uk/news/2014/january/non-repeating-patterns
  6. I dart with a guy who likes to throw underhand. The angle of impact is supposed to be more advantageous - essentially, the dart hits the board at the top of its arc - dead straight in.
  7. Well sure. There's lots of ways. Heat them till they turn to a gas, they will expand enthusiastically. Make sure they are made of chemically-active materials, then they will heat themselves, turn to a gas, and expand enthusiastically. If there's a hole in the chamber, they will attempt escape - again - enthusiastically. If that hole is at the opposite end of the ship from the cockpit, all the better.
  8. Yes. We simply call this reaction mass. You throw it out the back end of the rocket, and your rocket goes the opposite direction. The thing is, it doesn't get around the primary problems of rocketry: 1] storing all that mass (and thus moving it, as dead-weight) 2] accelerating that mass to a high velocity If the mass is not chemically active, then you need a device (motor) that accelerates it. And that device will need fuel to power it, Our solution is to use chemically-active mass. You don't need a motor to accelerate it - the energy is stored chemically within the mass itself - often
  9. Without anything external to push against or ejecting mass, you cannot make a craft go anywhere. Basic Newtonian physics.
  10. It doesn't matter what you use, or how you use it. You can't use magnetic fields to move a spaceship through space.
  11. If it were falling faster than its horizontal movement then it would, by definition, have a downward trajectory greater than 45 degrees. That would not be a good throw. (see attachment) No, at the peak of the parabola it has zero vertical velocity. As you release, the dart has its highest upward (positive) vertical velocity - and a constant acceleration downwards (negative), which immediately begins canceling the positive velocity. At the top of the parabola, all its positive velocity has been canceled by the negative acceleration, and it is momentarily vertically at zero v. (plea
  12. I do realize that. Which is why I wouldn't - and didn't - suggest such a thing. I was talking merely about the contact.
  13. I'm surprised to hear that darts of the same set would not have identical weights. That's a real quality issue. It's probably too late to take them back. You can buy tiny weights to add to your darts. This would be a far better solution than trying to compensate. The key to accurate darts is consistency. You don't want to be changing your throw all the time. To my eye, the thing that most confounds amateur dart players is that they don't realize how much the arc affects their accuracy. A dart that hits the board closer to horizontal will have a much higher probability of hitting near i
  14. This is kind of strange. Since you acknowledge that you can't tell the difference in weights, it follows that you can't adjust your throwing force to compensate simply based on weight alone. Is this actually about you manually throwing darts? Or something else? If it's really about throwing darts, then why not do the experiment? Get a few darts of differing weights, throw them, and plot what effect you get. You'll likely notice that heavier darts fall shorter than lighter darts.
  15. Awright. This is ridiculous. It's only been 13 hours!!!
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