HN user
It is some kind of failure that no part of this was preserved for scientific study, given the unique and non-reproducible nature of the ancient reactor. Such a loss!
I think there is a better answer than yet given to the iron bar question. Lets assume the bar is magnetized so the ends are north and south (as opposed to the weird thing, where it is magnetized through its thickness). Position the bars near to each other and perpendicular, like the letter 'T'. Now switch the bars' positions, so the other bar is the cross and the other the stem. When the magnet is the stem of the 'T' there will be a strong attraction between the pieces, while when the magnet is the bar of the 'T' there will be almost no attraction of the pieces. It is just like sticking horseshoe magnet to a piece of metal with its tips is much stronger than sticking it with its back, just now the horseshoe is straightened. The attraction is to the poles, not the equator.
Nope! :^) In the boat question, when the bolts are in the boat they are displacing water equal to their weight. After they drop to the bottom, they are displacing water less than their weight. So less water is displaced, i.e. total water level drops.
It seems pretty broken to me. When I zoom in far enough, it fades from the original zoomed pixels to a new image as per the design. But, unlike the design illustration, and unlike what one would expect from an infinite zoomer, the new image that fades in has no correspondence to the original. It should be that white pixels in the original correspond to mostly white images in next level image, and black pixels in the original should correspond to mostly black images in the next level image. But there is no correspondence.