# Water pressure in a tank

Nidum
Gold Member
even if I change L with 8.62 and h changes to roughly 5.75 I still get 2 when I calculate the Pressures in the way stated in post #46
That is correct . The pressure on the base is twice the average pressure on the side .

Anyway you don't need to work that out except possibly for your own interest . You just need to work out the volume of the water .

Regla
That is correct . The pressure on the base is twice the average pressure on the side .

Anyway you don't need to work that out except possibly for your own interest . You just need to work out the volume of the water .
ohhhhhhh, so that's AVERAGE pressure, makes some sense. But is there any way to make sure that h is actually 5.75?

Nidum
Gold Member
Work out the actual areas and pressures and pressure forces . If pressure force on the bottom is three times pressure force on the side then you have the right answer for h .

To complete this problem finally what is the actual volume of the water ?

Regla
Work out the actual areas and pressures and pressure forces . If pressure force on the bottom is three times pressure force on the side then you have the right answer for h .

To complete this problem finally what is the actual volume of the water ?
if the height of the water is 5.75 the the volume is 427 cm3 and the weight is 0.427kg. I also have to convert the weight into kilomoles, but I think I can handle it. thanks. If I'll have any problems while going over the whole solution I'll ask here, is that ok?

Nidum
Gold Member
That's the correct answer for the water volume - good result .

Certainly ok to ask new questions anytime .

Regla
That's the correct answer for the water volume - good result .

Certainly ok to ask new questions anytime .
since you're an regular visitor to this forum, what do I do that his post or problem would be shown as solved?

Regla
That's the correct answer for the water volume - good result .

Certainly ok to ask new questions anytime .
you made a small mistake (as did I) L is 40cm, 64dm3 is not 640cm3 it's 64000cm3. It's because we're dealing with volume not length.

Nidum
Gold Member
We are told that the total volume of the cube is 640 cm3 . If that's the volume then length of side is 8.62 cm . I don't know where you get all the other numbers from ?

haruspex
Homework Helper
Gold Member
64dm3 is not 640cm3
In post #1 you wrote 640cm3. Are you now saying that was wrong, that it is 64dm3?

Regla
In post #1 you wrote 640cm3. Are you now saying that was wrong, that it is 64dm3?
It was my mistake. I was stated that the volume is 64dm3 and stupidly stated that it's 640cm3 since I wanted it to be more applicable to people with imperial system to understand, I admit that I made a mistake, but the solution as far as I know doesn't change. it was a stupid mistake.

Regla
I made a mistake, L is 40cm, 64dm3 is not 640cm3 it's 64000cm3. It's because we're dealing with volume not length.

Nidum
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