How to jump from a moving train

Strategy #1: DECREASE

YOUR STARTING VELOCITY

If you jump from a train moving at 10 metres per second (m/s), you’ll hit the ground hard and fast. During impact, you will have a vertical velocity, because the train is higher than the ground. As you fall, the gravitational force will increase your vertical speed, as if you jumped off a stationary train. If the train is one metre high, you’ll travel at 4 m/s.

But keep in mind you’re also moving horizontally along with the train. So jumping would mean that upon impact, you’d move 4 m/s down and 10 m/s across. And it’s not the speed that causes injury, but rather the acceleration, or the change in velocity divided by the change in time.

Just as speed tells you how fast your position changes (or the rate at which something moves), acceleration describes how your speed changes in metres per second per second (m/s2). There isn’t just one ‘safe’ level of acceleration, but an acceleration of 10 m/s2 is safer than 40 m/s2.

To decrease your acceleration on impact, you need to decrease your starting velocity. If the train is travelling at 10 m/s north, you need to run 4 m/s south inside the train before jumping. Velocity is relative, so this puts your speed with respect to the ground at only 6 m/s north.

Strategy #2: INCREASE YOUR CONTACT TIME

Ideally, you’d use a sled to jump out of the train, so you could slide along the ground after jumping. But your next best bet is landing with a barrel roll. The key is to increase your stopping time to decrease your acceleration. No time for doctors when you’re on the run. – Rhett Allain