Why does a bag of chips make a "pop" sound when opened fast?

Question

How come if you open a bag of chips slowly there is no sound, but when air is forced out it results in a pop?

Answer 1

I assume it's because of the quick volume and therefore pressure change.

You smack your hands together on the bag and therefore the volume decreases rapidly. Because volume decreases, the pressure goes up. The pressure continues increasing while you are smacking the bag until the strength of the bag loses to the pressure of the particles. This is when the loud noise occurs.

Answer 2

You must be aware that a packet of chips has some gas <usually nitrogen> filled up so that it displaces the oxygen so via bacteria cant use that. Now when you open a bag slowly this air /gas flows out slowly in a steamline flow. Making little or no noise. When you open it fast or like comperess it the air inside is set into random motion. This produces sound (due to sudden motion and hence vibrations setting in)  because large volume of air passes out from the small opening. <you must have noticed that sound is produced in begining only>