All Questions
19
questions
2
votes
1
answer
101
views
Why does the bottle create vacuum inside if left closed?
I'm not 100% it's correct but it has happened to me a lot of times, I always close down a bottle normally with not too much tightness, with no liquid inside, and after a day it always is so hard to ...
- 69
2
votes
1
answer
459
views
Pressure cooker becomes pressurized again after closing and opening?
While cooking food in my pressure cooker today, I pulled the whistle using my spatula to let the steam off before I opened it to check on how well cooked the food was. Before, I opened the pressure ...
- 7,980
0
votes
1
answer
762
views
Does a tire deflate more quickly when not in use and why? [closed]
Answers from a google support the obvious; that tires goes flat when not in use, but when you read the answers carefully they allude more to that - yes a tire can still go flat when not used. My ...
60
votes
2
answers
6k
views
Why does pressure in a thermos increase after shaking up hot water and soap?
Whenever I wash my thermos, I put hot water and then some soap in; then I seal the one end with my hand or use the lid. After shaking it up, if I slowly remove the lid or my hand, it expels a little ...
- 581
0
votes
2
answers
5k
views
Is it dangerous to put a pressure cooker under cold water after cooking?
After cooking using a pressure cooker, it usually takes a while for the pressure to be released and for the cooker to be opened. However when I think the food may have been slightly overcooked, I take ...
- 163
0
votes
1
answer
329
views
Is force due to pressure equally distributed?
Pressure is defined as: $$P=\frac{F}{A}$$
My question is what if we want to find the total force in area of $\frac{A}{2}$. Would be equal to $\frac{F}{2}$? I think that is not true unless we know that ...
- 1,648
39
votes
4
answers
17k
views
Should a soda bottle be stored horizontally or vertically?
I am having an argument with my friend about how a nearly-full soda bottle should be stored in the fridge, with the goal of keeping the soda from going flat (i.e. keeping as much of the gas dissolved ...
- 520
3
votes
1
answer
441
views
Grooves on water tank
Why are there grooves on almost every water tank?
Just typing water tank in Google images would reveal what I am talking about. And here is a sample picture!
I think it would mostly be regarding ...
- 833
0
votes
1
answer
123
views
is boiling point of the gas cause cooling in expansion process of refrigeration?
I have a doubt about expansion process.
Some people say it's an adiabatic expansion, but other say it's something related to the nozzle.
What is the actual cause for cooling in expansion process?
...
- 191
-1
votes
3
answers
114
views
Why is there less oxygen in a pressurised plane that is flying?
Children who have temporary lung problems like asthma attacks have to go on oxygen to heal. (At a hospital.) Immediately after a health incident they can’t go on an aeroplane because there is ...
- 861
1
vote
1
answer
222
views
Holding one's breath while scuba diving
Recently when I went scuba diving, the instructor told me that it would be extremely fatal to a scuba diver to hold his breath during the dive. I searched up on the internet and came across Boyle's ...
- 3,745
-2
votes
1
answer
80
views
Why will crushing a water bottles keep the water in fizzy condition? [duplicate]
Everybody is talking only about CO2.
- 1
4
votes
1
answer
1k
views
Boiling of Water
I studied in textbooks that the boiling point of water is the temperature at which the vapor pressure is equal to the atmospheric presssure. My doubt is since the vapor mixes with atmosphere, how can ...
- 63
0
votes
2
answers
1k
views
Why pressure cooker is more effective in cooking than any vessel?
Why do we prefer cooking/boiling food in pressure cooker, I know there is a reason but don't know what is it?
I can't show my work here as it is a conceptual question.
- 1,829
4
votes
1
answer
309
views
Is there an ideal proportion for water to air in an espresso machine?
Let's imagine a very simplified espresso machine, and let's ignore the pump etc. and focus simply on the boiler. This is a metallic cylinder containing water, with a heater at the bottom, and a pipe ...
- 787