# Search results

1. ### Dissolved Air

I have a question regarding a project I am working with currently.... Air that is dissolved in water (there always is around 0,004% I think, in normal pressure and 20 degress celsius), is it "physically dissolved"? I mean is the dissolved air still gas or is just air-molecules "trapped"...
2. ### Air in water

I'm currently studying the phenomena of air bubbles in water affecting the sound (as it affects the speed of sound) produced in the water... I actually have a model for how the speed of sound should alter with the amount of air in it... but I've got som problem with a thing I found out...
3. ### Liquids with different densities

I have always wondered why liquids of different densities dont mix up if put together with caution. As if you have a glass halffilled with cold water, you can with caution add another layer of warm water above the cold. You will see a clear boundry between the layers. Is this something with...
4. ### Importance of zero

I know that the "discovery" (rather invention) of the number zero was revolutionary and is seen as VERY important... I've always had some suspicion to the zero by some unknown reason... I decided some weeks ago to figure out what it is that is wrong with the zero... So could someone please...
5. ### Speed of sound

If I have a glass of water and tap it with a spoon there will be a sound. If I change the speed of sounf by adding something the sound will change. What is the connection between change in speed of sound and the change in sound? Does the frequence change then or what?
6. ### Cool thing

Just wanted to share a cool thing I found when I was shown Eulers formula... e^(pi*i) +1 = 0 this can be written as e^pi = (SQRT -1)ROOT -1 dont know if I wrote correclty... ...
7. ### Introduced to the concept of entropy in school

Last we were introduced to the concept of entropy in school... I was quite suspicious to it already at first sight.. It is something like that in a closed system, chaos always increases.... meaningen that universe is heading towards chaos... (i.e. universe is heading towards where materiai...
8. ### 4 dimensions

Thougt of a thing, reading a topic about dimnesions... if we think like this... a point had 0 dimensions... there are infinite many points in a line (which has 1 dimension) there are infinte many lines in a square (which has 2 dimensions) there are infinte many squares in a cube (which...
9. ### Sound Problem

I read in a magazine the other day about a problem... You have a cup of tea. You start clicking with your tea-spoon on the cup and you put in som sugar. The sound of the clickings will change. Why? I guess that the sugar changes the density of tea, changing the speed of the soundwaves...