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Rocket Science

This week the science blogosphere has been spending a lot of time on space exploration and the science of understanding the universe outside our own planet. At risk of being the buzzkill distracting from all the cool space travel history and heated debates about NASA’s future, I think it will be interesting to do a…

We haven’t done an actual straight-up physics problem in a while, much less one above the level of undergraduate freshman physics. There’s a reason: it’s roughly as niche as it’s possible for an internet post to be. But on the other hand, surely someone ought to do it every once in a while. So here…

The Amazing Spider-Man!

Spider-Man, of mass 90kg, is perching 10 meters above the ground when he notices his (depending on the continuity) crush/girlfriend/wife Mary Jane (50 kg) being menaced by… I dunno, a menace. I’m more of a DC fan really. He swings down toward her to spirit her our of harm’s way. Assuming he starts from rest…

Earthquake!

Every section of Physics 218 I’ve taught this semester has asked me about this question. Really it’s less of a physics question than it is a math question, but either way it gives people fits. It’s not all that surprising. While it seems like it should be simple, to most beginning students it’s not at…

And the Cow Jumped Over the Moon

Poking around on the internet looking for interesting problems to assign the students I’m about to have this semester, I came across this one: How much energy must a 450 kg cow expend in jumping over the moon? Fig. 1: Buzz Cowdrin? Now hints and solutions are available on the linked site, so what I’d…