This is why Spiderman stretches every morning

Classical Mechanics Level 2

In the movie Spiderman 2 , there's a famous minute long scene where Spiderman stops a train. If the initial speed of a five-car, out of control subway train was around the top speed of the NYC subway (27 m/s), and Spiderman stopped the train in exactly one minute, then what is the magnitude of the force in Newtons that Spiderman exerted on the train as he stopped it?

Details and assumptions

A standard New York City subway car full of terrified passengers has a mass of roughly 40,000 kg.
You may assume the acceleration was constant and any other forces are negligible.

The answer is 90000.

1 solution

David Mattingly Staff
May 13, 2014

Spiderman stops the train from an initial speed of 27 m/s in one minute, so the acceleration is $a=(0-27)/60=-0.45~\mbox{m/s}^2$ . The force Spiderman exerted is then given by Newton's 2nd law, $\vec{F}=m\vec{a}$ . The mass of 5 cars is $5 \times 40,000=200,000~\mbox{kg}$ , and so the magnitude of the force Spiderman exerted is $F=|200,000 \times -0.45|=90,000$ Newtons.

This is why Spiderman stretches every morning

The answer is 90000.

1 solution

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