For trains the wheels and the rail are both steel, and the steel-steel friction coefficient is around 0.25. So the stopping time and distance will, at best, be three to four times greater than a car.
What object can stop a train?
– An anchor. The train probably doesn't have an anchor already, but a helicopter could drop one off. – Cranking the locomotive's steering wheel really hard to the right or left so the train veers off the tracks.