Wild Railroad Carriage

So I searched Wikipedia for the correct phrase, and it turns out that the things that make up a train are called railroad cars, or railcars for short (US and Canada), but in the UK it's railroad carriage... which is the expression I'll be using, because it sounds nicer.

Philippa Foot (1920-2010) proposed the following situation:
There's a wild railroad carriage going down a hill, seemingly unstoppable, and there are 5 people tied to the tracks... and you are there watching.

Luckily you notice a railroad switch, which can change the path of the carriage to another track, where there's only one person strapped to the track.

What do you do?

You switch the tracks; that's what most people would do.

So along comes Judith Jarvis Thompson (1929-), who puts a twist in the scene:
You have the train carriage coming at full speed, 5 people tied to the tracks... but there's no switch, only some people who are passing by who haven't noticed the carriage.

You grab a person and toss him in front of the carriage before it slices up the 5 innocent people into 15 pieces; the carriage gets derailed and the 5 people are saved, but the fellow you tossed in died.

Was that correct? If so, would making this decision be harder or simpler than the last one, when all you had to do was change the switch? In fact, was changing the switch the right decision at all?

I think it's a tough thought, hope you'll be at it and think about it some more, make new scenarios; it's easy to start wandering off to other ideas from this one.

By the way this is from a book called 30 Seconds Philosophy, which is pretty good at first sight, I've only read a part of the ideas in it, but it seems to be good and it summaries the ideas well.