I like to walk a lot, so naturally (naturally for a physicist, anyway) I have occasionally thought about the physics of walking. Here’s a simple calculation you can do. Imagine that a leg is a pendulum that swings at its natural frequency. First year physics tell you what its period of oscillation is. The length of the stride must be proportional to the length of your leg – if this isn’t obvious, draw a picture. So now it’s easy to figure out how walking speed depends on the length of the leg.
If you do the calculation, you’ll find that walking speed also depends on the acceleration due to gravity.
This is amusing, but do your results make sense? In other words, does this little calculation have anything to do with real walking? What about running? What about walking on the moon?
Post your thoughts as comments here. The best comment wins a very good (albeit slightly used) book of SF short stories (and yes, I’ll mail it to you if you live somewhere else!).
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The Apollo astronauts couldn’t maintain a normal stride on the moon. Not surprising given the bulky spacesuits and the abnormally high centre of gravity (many kg of life-support on their backs). So you would need a nice, pressurized base to test this. Where do I sign up?Now that I have proved to Peter that I am almost as much of a space buff as him, let me also note that this post reminded me of the Great Big Sea (from the tropical isle of Newfoundland) song “Walk on the Moon”, which I usually play in Astronomy 1021.