# Heated water in closed cylinder with electricity

1. Jun 28, 2009

### Joans

Hey, I guess I came to right sub-topic, since I knew here I may have not noticed every thing..

One sleepless night I was thinking about what would happen IF:
in a closed isolated cylinder would be alomost full of H20(+some salt if required).
anode and catode in sides, so what electricity would flow, (it's just a matter of engineering)
electricyti because of resistance would heat the water in amount of time given energy: UIt

so size allways is the same p1/T1=p2/T2 right?

But will water temperature and preasure would conitnue rising ? How?
And would it stay liquid or vapourize?

and for example in a bottom would be a valve or something what would open, and then because of running away preasure a cylinder would fly? :) In fact I tried to use example count and found that accelaration would be enormous, unfortunately I believe that I made some mistakes and considered to less thing, for example i dont considered vapourization(what should happen) and got equation:
a=(p1ST2-MgT1)/T1M OR a=(p1SUIt+cmT1(pS1-Mg))/cmT1M

p1- preasure at the beginning
S- area of the valve opening, for ex would be whole bottom
T2- water final temperature
M- mass of the whole rocket
g- I bet you know if not, better do not answer here
T1- water temperature at beginning
U-voltage
I-current
t- time
c- 4200 J/kg*K
m- mass of the water

So the problem might be unclear because English is not my born language, as you see...
Also some things might be called differantaly in different countries, like voltage (U, or V..) but physics is the same (:

So this topic involved all classical stuff: Mechanics, Electrodynamics, & Thermodynamics.

Main questions is how water would behave?

Thanks!

2. Jun 28, 2009

### Staff: Mentor

Don't try this at home:

And look at a steam table for what pressure and temperature are associated with each other as you heat the vessel.

Last edited by a moderator: Sep 25, 2014
3. Jun 28, 2009

excellent