Instead of using a complex electro-chemical reaction to convert water to some gas, I would like to see an analysis of a simple mechanical equivalent.

For example: consider a box with a volume of 3 units (cm, m, whatever). Inside this Box, on each end, are two smaller boxes, each with a volume of 1 unit.

Both this smaller boxes are connected via a spring.

The weight of the object could be 1 unit (1g, 1kg, 1 metric ton, whatever)

By use of energy we are able to extend the inner boxes. This way we can reduce the density of this object from 1/3 to 1/5.
The energy to reduce the density is stored in the spring.

In my opinion this mechanical object features the same basic attributes as you are using from the H2O-molecules.

Lets assume this object is submerged in an environment with a density of 1/4 (in g/m or kg/m).

In its extended state it will float up.
Since it displaces 5 units of volume, each with a weight of 1/4 It should experience an uplifting force equivalent to 5*1/4 - 1 = 1/4 units of weight.
Thats the weight difference between the displaced surrounding and the weight of our object.

On the way down our object will be in its retracted state.
Now the downward force is equivalent to 3*1/4 - 1 = -1/4 units of weight.

Lets assume our apparatus has a hight of 100 units of length (cm, m, whatever).

The energy gained on the way up should be force * distance = 1/4 * 100 = 25 units of energy.
On the way down we have a weight of 1/4 units.
E = m * h --> 1/4 units of weight * 100 units of distance = 25 units of energy.

So we have gained 50 units of energy, haven't we?

On the other hand: our object is ALWAYS submerged in the environment of 1/4 density.
How much energy do we need to switch our object from the retracted to the extended state?

As our apparatur is 100 units of length in height, the surrounding pressure on the bottom should be: p = rho * h.
p = 1/4 * 100 = 25 units of force.

To extend ONE of the two inner boxes we would have to spend 25 units of energy, to move the inner box outward against the surrounding pressure.
We are doing this for both boxes: voila 50 units of energy are used.


By using an electro-chemical reaction to change the density of your objects (H2O-molecules) you are obfuscating the need to use energy to change the density.

I guess you could complicate things furthermore by adding areas of different pressure.


The conservation of energy holds true for all experiments so far. That's why its called a law of nature - not because of some conspiracy.

Even if we observe some strange process where energy seems to vanish or appear: it is most likely we just don't understand the process.
For example: The neutrino was predicted because of an apparent loss of energy during radioactive decay.

Last edited by Momos; 04/27/10 02:51 PM.