Jump to content


  • Posts

  • Joined

  • Last visited

  • Days Won


swansont last won the day on November 19

swansont had the most liked content!

About swansont

  • Birthday May 12

Contact Methods

  • Website URL

Profile Information

  • Location
    Washington DC region
  • Interests
    Geocaching, cartooning
  • College Major/Degree
    PhD Atomic Physics Oregon State University
  • Favorite Area of Science
  • Occupation


  • Evil Liar (or so I'm told)

Recent Profile Visitors

155172 profile views

swansont's Achievements


SuperNerd (12/13)



  1. I agree, but we also know it doesn't work as advertised. And there's the issue of someone who is not well-versed in physics who is also simultaneously insisting on what the important physics concepts are. For all we know, the device works by heating the air around it, and it's able to direct the heated air in one direction, causing the box to recoil.
  2. It may be that you haven't studied the concept of center of mass yet. But that's not necessary in order to solve the problem
  3. In terms of thrust, and in terms of it being a transient at best, momentum is the key. Energy is a red herring. Unless the OP is more forthcoming about the device, I fear we are at an impasse. It will not work as described, and since we know the physics involved, it means the description is lacking - if it works. But we don't actually know this. We don't have a picture, or a video of a working device. Inclusion of these would not preclude chicanery, of course.
  4. Both masses will accelerate There is no applied acceleration This is not part of the problem. No, it's not. My advice to the OP is to ignore your post entirely. (if you want to discuss your misconceptions it should be done in a different thread) It's usually better to choose one coordinate system for the entire problem. In this case the motion of the two blocks are related, and you've introduced an easy way to make a sign error when you relate the two sets of equations. Extra care must be taken to keep track of the information
  5. ! Moderator Note Attempts to get you to follow the rules do not fall into this category. ! Moderator Note You don’t get to dictate the conditions under which you will follow those rules.
  6. A polarity reversal is what is meant by a flip. The N and S poles trade places. I don’t know what “flow” you are referring to. There is no “matter of the field” - it’s a field, which is not matter.
  7. https://www.usgs.gov/faqs/it-true-earths-magnetic-field-occasionally-reverses-its-polarity?qt-news_science_products=0#qt-news_science_products We can see evidence of magnetic polarity reversals by examining the geologic record. When lavas or sediments solidify, they often preserve a signature of the ambient magnetic field at the time of deposition. You should stop digging
  8. The earth’s magnetic field is not light. ! Moderator Note Please review rule 2.7 regarding using videos ti]onsupport your arguments You’re bringing up Cavendish out of the blue. Nobody should be required to have to figure out your tortured logic. If you can’t be bothered to explain, then we’re done here. Don’t bring this topic up again.
  9. You have to meet us partway. It’s one thing to explain why a model is wrong, but it’s too much of a burden to teach basic science on top of that. Which is the bulk of the work. The poles have flipped several times over the history of the earth.
  10. ! Moderator Note This is a place for discussing science. Either mainstream science, or some model you are proposing and can support with evidence. Not your opinion. Not untestable WAGs
  11. n is the index of refraction. We know that c is invariant and that it’s about 3 x 10^8 m/s, and depends on the permittivity and permeability of free space, by why those constants have those values is not known.
  12. If it’s enclosed it does not create thrust. All you’ve done is claim that it does. Work and momentum continue to be different things. Energy is not a vector. Force is. They are not the same thing. Instead of answering my question, all you’ve done is made a box in a diagram. What happens to the momentum? I am not asking about the kinetic energy. Also, please answer the other questions that you’ve skipped.
  13. Photons travel at c. Light travels at c/n One is a quantum explanation, the other is classical.
  14. The work is path independent, but the accumulated phase of the clock depends on the frequency and the duration of the trip. The dilation only tells you what happens to the frequency.
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.