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Recent content by AgainstOdds

  1. AgainstOdds

    Determining magnetic force at a distance

    Can someone point me in the direction of an equation to determine magnetic force at a given distance? I'm trying to determine what percentage of magnetic attraction or repulsion remains at a separating distance of 1cm, 2cm, 3cm, etc... Thank you.
  2. AgainstOdds

    How does inductive heating with magnets work?

    Thank you all for your help. I am still struggling to understand the concept of inductive heating. I can see how alternating magnetic feilds could be a problem, but as in my application, all magnets will be oriented the same way. That is, one magnet will pass another, and the next magnet that...
  3. AgainstOdds

    How does inductive heating with magnets work?

    MJR2 - thanks for remembering my previous post. I wasnt quite sure how to relate the two questions without being extremely wordy or confusing. I'd like to change the scenario a bit though. Same inner cylinder, roughly 12" in diameter and 70-80 magnets attached to the circumferance. But this...
  4. AgainstOdds

    How does inductive heating with magnets work?

    So the degree of heating taking place is dependant upon the strength of the magnetic field and the frequency at which the conductive material being heated is passing through the magnetic field, correct? Does the positioning of the magnetic fields have much effect? For example, from what I've...
  5. AgainstOdds

    How does inductive heating with magnets work?

    I've been trying to learn more about inductive heating to try and answer a few questions of mine concerning the amount of heat generated by magnets passing through opposite magnetic fields at a high frequency. Does inductive heating heat from the inside of a conductive material outward, or does...
  6. AgainstOdds

    Time before demagnetization?

    Let's say 70 of the above listed magnets were attached to the outside of a 11.5" O.D. cylinder in a fixed position, and 70 more of the above listed magnets were attached to the inside of a 12" I.D. cylinder which could be rotated around the inner fixed cylinder. If the outer cylinder were spun...
  7. AgainstOdds

    Time before demagnetization?

    MJR2: Thank you for your reply. How much heat are we talking about producing? Will it likely be more than could be compensated for by a simply cooling system, or could it be managed if the magnets were only operating at 5-6kHz? MagMike: I do indeed have a project that I am working on. My...
  8. AgainstOdds

    Time before demagnetization?

    Thanks for your help, sreid. Would it make any difference as far as demagnetization is concerned if the magnets were passing through multiple magnetic fields rapidly, say at a rate of up to 10,000 fields per second? (I apologize for my seemingly insane questions.)
  9. AgainstOdds

    Time before demagnetization?

    Awesome, thank you for your replies. I'm assuming if I used the same magnets in a repelling orientation (N-N or S-S) then I would see a decrease in their magnetic fields over time because each magnet would try to reverse the polarity of the other, correct?
  10. AgainstOdds

    Time before demagnetization?

    If two neodymium magnets were held north to south with 1cm separating them, how quickly would they demagnetize under the following conditions: - Average temperatures (say -10 to 130 degrees F at the extremes) - Exposed to air - high pressures (possibly spiking to as much as 400psi)...
  11. AgainstOdds

    Force of attraction and repulsion equal?

    Thank you for your replies.
  12. AgainstOdds

    Force of attraction and repulsion equal?

    I've been doing some searching and I've found some information that seems to suggest that magnets exert a slightly higher attractive force than their repulsive force, when dealing with two identical magnets. For example, two magnets placed N to S would exert more force on each other...

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