All Questions
9
questions
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
1
answer
36
views
Sound made by trapped water
When I run water in my bathroom sink and then put the plug in whilst there is still some water left in the basin, there is a high pitch moaning or screeching noise made by my adding the plug. What ...
- 406
1
vote
1
answer
994
views
Why does a cup on water layer create suction?
When I place a cup upside down on a layer of water, say a wet table, and I then try to lift the cup up, I can feel some resistance. So the cup is acting like a suction cup.
However the difference is ...
- 4,576
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
-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
1
vote
0
answers
406
views
Is it possible to breathe deep underwater with a pipe if enclosed in a box?
A problem in the physics textbook I was using asked how deep someone could go underwater and still manage to breath through a strong pipe or hose, assuming that the maximum pressure difference the ...
- 127
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
3
votes
1
answer
492
views
Does tapping at the side of a bottle prevent shaken soda from bubbling over?
Anecdotal evidence has it that a bottle of soda that was heavily shaken will not bubble over if tapped at the side multiple times.
Yet I wonder: Has the tapping really any effect? Or could it be that ...
- 170