3 ms·

I just found it funny that the author uses such a specific measure for an object that typically looks nothing like a credit card. I think the only credit-card s

I just found it funny that the author uses such a specific measure for an object that typically looks nothing like a credit card. I think the only credit-card sized magnet I've ever seen might have been an elastic magnetized floppy piece of plastic that was rather weak (I think it was used to fix paper on sheet metal). How about "even a small magnet can pull up things and overcome the gravity caused by a whole planet's worth of mass"? BTW the comparison to the strong and weak nuclear forces is sort of strange too because not only do they only matter on nuclear scales, they also behave strangely not to an inverse-square law; Don Lincol of Fermilab explained that in a Feb 2024 video[1], from the description: "Popular science explanations [...] claim that some of the forces are stronger than others. What they don’t tell you is that all of those claims are only valid for distances comparable to the radius of a proton. For different size scales, the order of the strength of the forces can be wildly different."

tsimionescu 2y ago
Credit-card shaped and sized magnets are actually pretty popular as tourist mementos. It's true that they are typically slightly smaller than a credit card, but they're a common occurrence. And while it's true that the strong force has very complex interactions which make it both stronger and weaker than EM in certain situations, I don't think there is any situation in which EM is weaker than gravity. Of course, the comparison is ultimately apples-to-oranges, as it basically amounts to comparing the amount of electrical charge to the amount of "mass charge". Still, if we compare by, say, the total number of particles with mass/charge respectively of any kind you need two bodies to have to have an equivalent effect on motion through gravitational VS EM interactions, in every situation that we know how to model, you would end with the same conclusion.

tsimionescu 2y ago

Credit-card shaped and sized magnets are actually pretty popular as tourist mementos. It's true that they are typically slightly smaller than a credit card, but they're a common occurrence. And while it's true that the strong force has very complex interactions which make it both stronger and weaker than EM in certain situations, I don't think there is any situation in which EM is weaker than gravity. Of course, the comparison is ultimately apples-to-oranges, as it basically amounts to comparing the amount of electrical charge to the amount of "mass charge". Still, if we compare by, say, the total number of particles with mass/charge respectively of any kind you need two bodies to have to have an equivalent effect on motion through gravitational VS EM interactions, in every situation that we know how to model, you would end with the same conclusion.