Archive for category video
The mirror puzzle
Posted by Michael Beach in optics, video on May 31st, 2010
Somehow, a mirror ‘knows’ to swap left and right, but not up and down.
Ok, stand in front of the mirror and it swaps left and right – you wiggle your right hand, the left hand wiggles in the mirror. But, up and down don’t get swapped, the top of your head is still at the top. More puzzling – when you lie down, the mirror still ‘knows’ when you right hand moves, and ‘shows you’ a left hand moving. Asking a few good questions leads to the real answer. Here’s another Feynman video. Enjoy.
Feynman explains how trains stay on track
Posted by Michael Beach in video on May 31st, 2010
In this short video, physicist Richard Feynman describes the fun of figuring out how things really work. The example he uses here is how trains stay on their rails.
No, it’s not those flanges (though that seems obvious at first). In a way it’s a kind of ‘closed loop servo system’ or a self-correcting mechanism. In mechanical design I’ve heard this idea called ‘self-help’ where loads get distributed evenly by a careful design (see the book The Elements of Mechanical Design by James Skakoon for more on this topic).
This shows a microcosm of the job we do working with clients, solving problems – we always care about how things really work, and this video shows an example where the first ‘obvious’ idea may not be quite right.
In any case, it’s always fun to hear Feynman explain stuff. There’s a load of footage of him at youtube, explaining fire, light, uncertainty. Enjoy.