initial speed

As far as meaty physics goes, The Bourne Ultimatum is a standout among action flicks. Compared with other pillars of the genre, like Mission Impossible and XXX, Bourne sustains some impressive dramatic excitement without succumbing to the patently ridiculous.

It's not hard to suspend disbelief during the movie's dizzying quick cuts, but Jason Bourne's Superman-like physical capabilities are a little suspect. He has astonishing reaction reflexes, infinite physical stamina, and the ability to withstand an amazing quantity of forceful blows, impacts and collisions without sustaining much more than a few scratches and an intermittently gimpy leg—pretty unlikely stuff, even for an elite assassin.

But we're not here to criticize the improbable. Why else do we go to action movies, after all? That said, there is one interesting physics moment that I feel obligated to point out: a motorcycle chase scene in which Bourne tries to prevent a CIA assassin from snuffing out the closest thing he has to a romantic interest. While taking a short cut, Bourne jumps his motorcycle over what appears to be a six-foot concrete wall. Fans of XXX may not bat an eye—Vin Diesel's grasshopper-esque, unassisted leaps over a 30-foot fence, a guard tower and a house, all without the assistance of a ramp of any kind, make Bourne's paltry six-footer look like a bunny hop. Nevertheless, it's worth taking a look at the numbers. Just how much force must he be capable of exerting on the ground to get him over the wall?