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In the 2004 film Spider-Man 2, the titular superhero uses his web to bring a runaway train to a standstill, saving the passengers from a watery death…
But if Spider-Man’s web was made from real spider silk, would it have halted the train, or would it simply have snapped under the tension? Three physics students at the University of Leicester recently decided to find out.
First of all, they calculated the mass of the train, assuming that the four New York City Subway cars shown in the film were full of passengers. Then, knowing the maximum velocity of NYC subway trains, they calculated the train’s momentum.
This allowed the physicists to work out how strong Spider-Man’s web would need to be in order to bring the train to a halt before it plunged into the river below. They found that the web would require a Young’s modulus – or stiffness – of just over 3 gigapascals.
That may sound like a lot, but real spiderwebs are just as strong. The web of an orb-weaver spider, for instance, can have a stiffness as high as 12 gigapascals. So, if spider silk was scaled up to human proportions, it really would be able to stop a rampaging train!