Answer :
When you are at a higher altitude the air pressure is lower as there is less air the higher you are.
This is why if a plane's window was to break, the items contained in the plane would be sucked out as the pressure outside the plane is less than the pressure inside the plane (the plane has more air inside it than outside).
This is why if a plane's window was to break, the items contained in the plane would be sucked out as the pressure outside the plane is less than the pressure inside the plane (the plane has more air inside it than outside).
