sorry

okay so i don't know if this is physics, i kind of have a feeling it might be chemistry...but okay. so we were in these dorms at a community college for states and so it was like there were 4 beds, 2 on each side. So there were like two rooms and then in the middle was the tv, kitchen, living room or whatever you want to call it. So we were in the middle room and then one door to one room was open and the other door to the other room was closed. one of the girls from a different room came into our room to sleep for a while so she went in the room (the one with the door opened) and then she closed it so she could have peace and quiet. So when she did a few moments later the other door that was closed opened! i was freaked, but my friends told me that it was the pressure that made the door open. =]