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Raffaele
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<Moderator's note: Moved from a technical forum and thus no template.>
My daughter, who attends the italian equivalent of US K9, asked me some advice about a physics hydrostatic problem.
> Which pressure (in atmospheres) a fireman must use to send water at 12
> meters height.
I tried to use the definition 76 cm of mercury is 1 atm and I made the proportion between water and mercury densities
Namely
if with a density of 13.5
atmosferic pressure raises Hg to 0.76 m then the pressure of 1 atm raises water to 13.5\times 0.76 m that is 10.26m.
Thus to arrive to 12m the pressure required is 12/10.26=1.17 atm
But the book says 2.2atm
Can you, please, explain what I did wrong?
Thanks in advance
My daughter, who attends the italian equivalent of US K9, asked me some advice about a physics hydrostatic problem.
> Which pressure (in atmospheres) a fireman must use to send water at 12
> meters height.
I tried to use the definition 76 cm of mercury is 1 atm and I made the proportion between water and mercury densities
Namely
if with a density of 13.5
atmosferic pressure raises Hg to 0.76 m then the pressure of 1 atm raises water to 13.5\times 0.76 m that is 10.26m.
Thus to arrive to 12m the pressure required is 12/10.26=1.17 atm
But the book says 2.2atm
Can you, please, explain what I did wrong?
Thanks in advance
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