# An Electric Pickup Truck Really Could Pull a Freight Train—Here's How

Wired | 7/30/2019 | Staff
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In a recent stunt, a Ford crew hitched an all-electric F-150 pickup truck to a freight train filled with 42 more F-150s. Then a driver hit the throttle, and the pickup truck towed the 1.3 million-pound train. This raises some interesting questions. How hard is it for a truck to pull a train? Is that even possible? Could a normal truck do this? Of course it's an impressive feat—but the real limiting factor is friction.

Let's start with a more idealized situation. That's what we do in physics—when something is potentially complicated, we make the scenario less complicated to make sure we are on the right track.

#### Train - Case - Friction - Answer - Force

So, what would it take to pull a giant train in the case of zero friction? The answer is that any tiny force would move the train. Even an ant could move it. Yes, this is true—it just seems impossible because you've never encountered a situ­ation with zero friction. Here is a force diagram for a tiny object pulling a massive object with no friction. I'm going to use boxes to represent the objects, but if you squint real hard you can make that box look like an ant.

That diagram might look complicated, but it's not too bad. Let me go over all the details. The first thing that might seem puzzling are those arrows over some of the symbols. You don't really need to know about those, but that means those quantities...