Hello! I've got a question for you guys. A friend of mine told me this: If someone is travelling in a transparent train and drops a coin (standing on his feet, whatever this has to do with anything), for him, the coin would go straight down, but for someone standing outside the train as it goes by, the coin wouldn't fall only straight down, but also in the trains moving direction making the coins movement look diagonal.
I think this is wrong as the coin still relates to the guy dropping it, and therefore it will look like the coin is going down in a straight line or else it would land some feet in front of the dude inside the train, which makes no sense at all.
Well, who's right and who's wrong? I'm not very knowledeable with physics so I'd like to have someone explain who's right and why.
Thanks in advance and sorry for my bad english (it's not easy for a kid living in Sweden with swedish as his native language instead of "la lingua pura" ).