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swansont

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Everything posted by swansont

  1. The force exerted by light is F = P/c (where P is the power) for absorption, and 2P/c for perfect reflection. You need P = mgc/2 which, for just 1 kg, is a little less than 1.5 Gigawatts. At the distance of the earth, sun intensity is around 1.3-1.4 kW/m^2, so you need around a million square meters. And you’ll likely fry the solar sail, because you don’t have perfect reflection.
  2. Work is not force. Force is directly related to momentum, not KE The relevant quantity is momentum. KE is generally not conserved these kinds of collisions. If you magically cut the speed in half, you reduce the momentum by half. That directly correlated to the recoil after impact. Describing a box moving a certain distance after impact assumes other factors - the box will keep moving absent other forces being present - and you are not actually analyzing the collision. You’re just waving your hands. The example you gave earlier had no reduction in momentum, so there’s no inherent change in the dynamics. No, that’s not what would happen. The box would only move back if the ball moved back to its original position. The CoM never moves. How do you slow it down? Where does the momentum go? What you’ve described is magic, not physics.
  3. ! Moderator Note Can’t say you weren’t warned Don’t bring this up again
  4. This is all moot, since I was talking about manufacturers (plural) in competition for market share. You can compete on quality or price or possibly intangibles (prestige). But it’s predicated on competition. Even so, selling just 3 million over 25 years means most people were not buying this car.
  5. ! Moderator Note But you are preaching your pet theory, not asking about mainstream physics. Pick one. Ask questions to learn physics, or give us your model and evidence to support it.
  6. Point taken. I was thinking in terms of a market economy. edit: Still, an average lifespan of 28 years sounds like it supports my point
  7. I have no idea what that is. edit: according to Wikipedia, it was cheap and reliable, and about 3 million 601’s were sold over ~25 years.
  8. Math. -1e +1e = 0 You’re just making stuff up, and it’s proving tiresome
  9. Electricity and magnetism is real physics. The wave equation is real physics. You haven’t demonstrated any understanding In a word, no. If you are claiming this, you need a model and evidence. If you keep engaging in the rectal reach protocol, this will be closed.
  10. I agree with zapatos. People won’t buy cars that are known to break down. Manufacturers have a vested interest in some level of reliability. You can get that with quality control, and also with redundancy. If a part shows that it’s near end-of-life then you don’t need redundancy (tire tread, for example) If it’s life-preserving, often you do (brakes on more than one wheel)
  11. Sorry, but joigus is right. You are vastly overestimating your understanding of physics
  12. No, you cannot. Making stuff up is kinda the opposite of science. Sure we do. The speed of an electromagnetic wave from Maxwell’s equations is c
  13. I doubt such a citation exists; it’s like proving a negative. Emergency backups working as planned isn’t newsworthy. But we hear about such failures when they occur. When hurricane Sandy hit the US east coast some years back, gasoline and diesel supplies were impacted, because the refineries and terminals were without power. So generators couldn’t be replenished once the fuel ran out. No gas/diesel for trucks to move fuel to critical customers. This was news, because it was a failure of unanticipated duration. I imagine this caused a re-think of emergency procedures, as would the scenario you describe. I know we have at least one thread where that idea is shown to fall well short of being self-sustaining (and I notice the article provides no analysis). A few added km of range, yes, but nothing more.
  14. The plane is a description from Newtonian physics, which is adequate to explain the vast majority of the behavior of the orbits. Much in the same way as we use classical physics to explain things and not invoke negligible quantum effects.
  15. The KE doesn’t matter; at 45 degrees the momentum is smaller. KE doesn’t directly correlate with the force
  16. I don’t see where you stated that. This will change the mass distribution; the box would move but the center of mass would not. How do you reduce the KE before it hits the rear of the box Does it continue forward after the stream is turned off?
  17. ! Moderator Note Discuss freewill as you wish, but you need to do it without proselytizing.
  18. Providing more evidence than just your say-so would be job 1. If it’s reactionless, then it violates conservation of momentum. You are misusing the terminology. And have not described the device.
  19. Claiming this means you reject relativity, because there are no absolute frames in relativity, and relativity allows you to compare the observation of different frames. You would need to provide evidence of this absolute frame. Which has nothing to do with being “in reference to the universe” It’s just your motion relative to the source Repeating this doesn’t make it true. Why can’t you provide experimental evidence to support you claims? What does this mean?
  20. Right. So you should be able to set up equations for the forces on each block.
  21. What does the third law tell you about these normal forces?
  22. Gauss’s law works because the potential for a point charge is 1/r (all other configurations are superpositions of that). I suspect that’s not the case for the Higgs.
  23. ! Moderator Note The topic was how to pray. It was not an invitation to bash beliefs
  24. I see you have mg and N; I’m not sure why you would include a fictitious force. mg acts down (-y), and N has a y component and an x component. What can you say about the normal force that m exerts on M, and that M exerts on m?

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