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Physics/Black Hole Experiment


Dr. Nelson, I set up the black hole collision fish tank experiment as per your instructions, however, one problem arose, the pumps are not strong enough to create an attraction between the two intake tubes. It would appear that 3.5 gallons per hour, even in a 5.5 gallon tank is not sufficient to create a collision or even orbiting of the two intake tubes. I am now trying to find stronger pumps and was wondering if you might be able to suggest anything else that could be the cause of the failure of the intake tubes to attract each other.

Hmmm...too slow?  You could try putting the tank up high and do one-shot experiments where you use a long siphon to drag the water out faster...feeding in from the top from a reserve tank, if necessary.  Otherwise, it does appear you need a bigger pump.  Perhaps a "swamp cooler" pump (in a home improvement store, they drive evaporation-based air conditioners for houses) or similar pump, or even something like this:


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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