Put a stainless steel glass on your mouth and suck air from it. It will stick to your mouth. Why?
Answers
Answer:
As you know the atmospheric pressure is 1 bar. This means if you have an open bottle, the pressure inside is the same as outside which is 1 bar. Also, if you close that bottle, the pressure inside the bottle will again be 1 bar.
Now lets take the air out of that bottle. Put your mouth on it and start sucking the air out of the bottle, you will see the bottle crumpling.
What exactly happens is that when you suck the air, the pressure inside this bottle will drop as there will be less air in the bottle. This happens when sucking only. But the crumpling happens because the pressure outside the bottle become greater than the inside of this bottle. Once the pressure outside is higher than inside, the air on the outside will squeez down on the bottle crumpling it up.
If the bottle was glass, if you suck the air out, nothing will physically happen to the bottle because it is solid. But the pressure inside the bottle will drop, and when pressure drops inside, the air on the outside will squeez the glass, but the glass can resist this force making it look like nothing is happening.
Hope you understood, good luck
Answer:
put a. stainless steel glass