Given that:
Water of depth 10 m exerts a pressure equal to atmospheric pressure.
An air bubble reaches the surface of a lake which is 20 m deep.
How can we know that the pressure at the bottom of the lake is 3 times of the atmospheric pressure? I am rather clueless...
Thanks. Your help would be great.
2006-09-06 00:47:46 · 4 answers · asked by unquenchablethirst 2 in Science & Mathematics ➔ Physics
Andy is wrong and you are more or less correct.
At the surface of the water, you have 1 atmosphere pressure (we will accept 1 Bar, although it is not totally exact).
Every 10m column of water equals 1 Bar as well.
So, at 20m, the pressure is 3 Bars (1 Atmosphere or 1 Bar + 20m of water or 2 Bars), or 3 times the atmospheric pressure.
For the info:
A Bar is a constant pressure, and so is a Pascal. One Atmosphere is not: it is more or less equal to a Bar, but it varies all the time!
Same for water: the pressure exerced by the water depends of the salinity of the water, so in fresh water, 10m makes 1 Bar, while in the sea it is around 9.95m for a Bar (salt water is denser).
2006-09-06 01:04:19 · answer #1 · answered by just "JR" 7 · 0⤊ 0⤋
First off I believe the pressure of water at a depth of 10 m is far greater than atmospheric pressure. That's why my ears start to hurt at only a third of that depth...
But in answer to your question, the volume of the bubble as it reaches the top (atmospheric pressure) is three times the volume it took up at the bottom meaning that the pressure at the bottom was three times as great as the pressure at the top...
2006-09-06 00:56:02 · answer #2 · answered by Andy FF1,2,CrTr,4,5,6,7,8,9,10 5 · 0⤊ 1⤋
THE PRESSURE AT THE SURFACE OF LAKE=I ATMOSPHERIC PRESSURE.
THE PRESSURE AT 10m DEPTH=2 ATMOSPHERIC PRESSURE
THIS IS BECAUSE 10m DEPTH OF WATER EXERTS 1 ATMOSPHERIC PRESSURE ,BUT THE PRESSURE AT A DEPTH OF 20m WOULD BE THE SUM OF THE PRESSURE AT THE SURFACE AND THE PRESSURE AT THE DEPTH OF 10m WHICH IS EQUAL TO 2 ATMOSPHERIC PRESSURE .SIMILARLY IF WE WOULD GO 10m FURTHER(i.e,we are at 20m depth) THE PRESSURE =2 ATMOSPHERES+1ATMOSPHERE(THIS 1 ATMOSPHERE IS THE PRESSURE EXERTED BY THE WATER AT 10m) WHICH IS EQUAL TO 3ATMOSPHERES.
2006-09-06 01:11:09 · answer #3 · answered by prince_1993 1 · 0⤊ 0⤋
In scuba diving the atmosphere will increase 1 atmosphere for every 33 ft. u go down.
2006-09-06 03:28:42 · answer #4 · answered by JOHNNIE B 7 · 0⤊ 0⤋