An ecological gravity wheel

[path_finder]

Hereafter is an spherical aquarium, with a rotation axle in its center, not full filled with water (in view to keep the COG under the axis).
We suppose this aquarium populated with some male red chinese fishes.
Normally the distribution of the fishes inside the sphere is ramdom. IMHO the aquarium should be keeling always.
But this shot has been taken just after the apparition of a female at the right side of the aquarium (not represented).

Question: in what direction this aquarium will rotate?
1. counterclockwise
2. clockwise
3. neither (no rotation at all)

This is a serious question, because here are some sources of energy (the fishes), and the principle of conservation is hard to apply.
In addition what happens if some food is given to the fishes: will the rotation speed be increased?
What will be the swimming effect?
IMHO a practical test could be very useful. But I'm far from home (now in Yaounde/Cameroon) and there is no aquarium in my hotel.

[azimuthe]

Hi all

The direction of rotation depends on the mass of water displaced by the fish.
If their mass is equivalent to the weight of water displaced nothing running.
if the fish are heavier than water, they will fall into the bottom of the aquarium if they are lighter they will float to the surface.
the ability of most fish is to keep them in the desired amount of oxygen so that it is in equilibrium in water.
So certainly no rotation

cordialy.

[murilo]

p_f, hi!
I bet as in a few minutes our Nickbordeaux will link this design to a dozen of ping-pong balls...
I bet! 8)
Best!
M.

[DrWhat]

Another question could be if you push a balloon down into the same area of the fish (no fish) from the top, what would happen.

All forces equalize of course!

[nicbordeaux]

Murilo, Path is having his fun, that's in good order, and the question is an interesting one given the variable, eg the pheromones nobody picked up on. All I can say is that if my OU washing bowl starts pushing out MW, some people are going to pay more for their free energy than others ;)

Come to think of it, are pheromones a conservative force ? Do they, like some wavelengths, travel though matter, in this case the fishbowl ?

Edit: it's a good question : ok, the density/weight of the fish will determine position "verically" in the bowl, but any movement will displace water. Furthermore, if the fish sink to the bottom of the bowl (their air bladder is unfortunately not working), in the illustration of PF the COM of the system will be lowered, meaning as the fish are right of vertical axis, the bowl will keel over CW. What is important is not just the final equilibrium as in the baloon example of Dr What, but the water displacement, which is mass displacement within a container.

Now, where have I put the remaining 71 pingpong balls ?

[murilo]

Nic,
let's wait for him come back to home, when he'll reach the normal rates about pheromone evaluations.
The best way to met male red fishes is to put in water a female worm. 8]
Bon voyage, Mer Path!
M.

[nicbordeaux]

A worm in front of the goldfish like a carrot in front of a donkey. Good thinking Murilo.

Again, the question asked is interesting because of the behavior of water. Theoreticaly all fish fall to bottom of bowl in a even spread mass. But as they are to right of center, they will tend to accumulate in a pile to right, overbalancing the right a bit, therefore CW.

But the main point IMMO (is IMVUO as in "in my very uninformed opinion" an accepted internet accro ?) is that there is action reaction with unequal reaction times : any force created or caused by mass sinking will "hit" the right side of tank well before the more distant left side. So again, we have a latency.

[Trevor Lyn Whatford]

To the 3 wrong answer members I have one question, do you want to buy my one reservoir water wheel? one not very careful owner little used : )

Regards Trevor

[Gwheel]

path_finder,

The male red Chinese fish, also known as Asian arowana are endangered under the Endangered Species Act, it is highly illegal to own them. Contact the Department of Interior immediatly.

This picture is surely fake! The mode of reproduction of these fish is almost certainly ovopartity. These fish lay undeveloped eggs, leading to external fertilization (90% of bony fish). The fish determine the location of the unfertilized eggs by chemoreception.

Conclusion: The fish will be randomly distributed within the bowl (not being attracted to the female) and it won't rotate. Wait ! ... path_finder, is this another bowl joke... an April Fool's bowl joke?

Regards,
Chris

[murilo]

For the design the water behavior will be the same WITH or WITHOUT those male fishes - all them with apparent density =1g/cc.
If they are lighter, they will buoy and heavier will sunk.
In all cases, the water will present a medium distributed rate, as ever.

What worry me are all those male fishes with a single arowana girl!
Best!
M.

[tismooothy]

If the fish are algae eaters with there suckers stuck to the side of the bowl and they inflate there air bladders at seeing the girl fish then counterclock wise if they deflate there air bags clockwise