Please Can Someone Help!

[benny3008]

Right, this has been driving me mad all day and if anyone can come up with a scientific answer (in simple terms) I would be very happy.

Imagine you have an articulated lorry, a bus, whatever, just an enclosed moving vehicle, you're inside it and the vehicle is moving...you throw a ball in the air, does it...

A. Fall straight back down into your hands or...
B. Stay put and land on the floor further back in the vehicle.

Asked my mum this earlier and she said well of course it would land back in your hands, so instead of a ball, I changed it for a remote control helicopter, or similar, hovering in the air at a set point, vehicle moves forwards, what happens to the helicopter, stay in position within the vehicle or stay in position with relation to the outside world?

What do you think, or do you know the answer?

[ImLostAgain]

This always reminds me of a question asked when I were but a lad. If a steam train is going at 100mph and there is a 100mph wind blowing in the same direction, which way does the steam go.
It did my head in....but that was me.