During the school holiday, I brought my family to Genting Highland to escape the heat from Penang island. Geographically, Genting highland is a mountain peak of Titiwangsa Mountains. It is situated at an altitude of 1800 meters above sea level. Therefore its air pressure is lower than at sea level.
At the hotel room, my son suddenly asked me one scientific question, " Why the potatoes chips pack so big? ". I replied, " It was due to difference of atmospheric pressure".
At sea level, the atmospheric pressure is the highest. Therefore, you will see a smaller pack of chips.
At the peak of Genting Highland, the atmospheric pressure decreases in tandem with higher altitude. At 1800 metres altitude, air pressure inside the chips pack is greater than the outside atmospheric pressure. Difference of pressure produces a resultant force to push chips pack outward. Hence, the chips pack expanded.
After I explained air pressure lesson to him, he puzzled. I don't think he could understand what I taught him about atmospheric pressure concept. How about you, my dear students ?