ELI5, why if you jump inside a moving train you will land on the same spot, but if you jump on the roof of a moving train, you land on a different spot?

Question

seen it on twitter and I can’t get my head around it
EDIT: thanks guys I get it now 😅

In: Physics

Answer 1

Inside the train the air is not moving relative to you. Outside the train it is so it will blow you back. Like when you stick your hand outside a car window.