# ScienceNostalgia101

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1. ## "Number of turns of wire..."

My bad. I guess I'll have to brush up on my electromagnetism to get the full context for this discussion, then.
2. ## Harnessing the energy of forest fires

The idea was to build it prior to the forest fire, in anticipation of where they typically are. @ HallsofIvy The twin towers weren't filled with water, though. Wouldn't water flow to wherever the water level was dropping in the pipe? If not, why not, and if so, why wouldn't that constant contact between water and steel resist temperature increases beyond the boiling point of water? @ Area54 I have no idea how much it costs to build an elevated pipe or a wider, more rectangular container of water, nor where to start on that one, so I was hoping someone more familiar with either could fill me in on this.
3. ## Why cant light be stored?

Here's one out-of-curiosity question, similar to Raider's but without the "one way mirror" to consider. If someone made a closed container, coated on the inside with the most reflective material possible, and put a laser pointer inside it (set to go off at a given time) and used up all its light to completion, where would the light go? Would it all be absorbed/transmitted, even by whatever degree of either it has? And would reflectance give way to absorptance and transmittance once the intensity of light increased?
4. ## "Number of turns of wire..."

I've seen a number of formulae in electromagnetism refer to the "number of turns in a wire;" not some function that converges at infinity, but rather linear proportionality. (To things like magnetic field, magnetic inductance, etc...) I get that, in practice, once a current carrying wire generates a magnetic field, this creates a back emf and decreases current to some equilibrium level. But in that initial instant; when the current begins to flow; does this mean you could have a theoretically infinite magnetic field/inductance/etc... with enough turns of wire?
5. ## Harnessing the energy of forest fires

Year after year, somewhere in the world, its forests are on fire. There's a lot of talk about people displaced, but not about energy that went to waste. Is it at all possible to set up a network of pipes carrying seawater, (and/or giant enclosed containers of the stuff; obviously not tall, just long and wide) such that any burning forests underneath them would force the resulting water vapour into a pressure release valve underneath a steam turbine? Apart from any initial investment in such a project, would there be significant maintenance costs?
6. ## Hydrogen-based fireworks?

Eh, it's fine, turned out my hometown went ahead with that municipal fireworks display after all. Forgot all about this thread after that until now. Another question, for future reference; would glass store the hydrogen more effectively? If so, and if I put a balloon full of air over the tip of the bottle, would it become 50% hydrogen by diffusion? (Or alternatively, more than that because hydrogen is lighter than air?) And even if so, would there be a way to get the concentration higher than 50%? Would a tube of water inserted underneath the balloon, filling the bottle, force hydrogen into an empty balloon wrapped over the tip?
7. ## Hydrogen-based fireworks?

I've got a whole bunch of half-drained batteries and wood ash around, and I was considering making homemade hydrogen-based fireworks with electrolysis for Canada Day. 1. I tried testing the wood ash for hydroxides by putting them in an aluminum can and mixing them with water, but it didn't dissolve the can. Are carbonate compounds effective enough electrolytes? Are they safe to use? 2. Do balloons store hydrogen reliably for days? If so, does it depend on the material? If not, do you know of what else can be used to store them that can also be used to pump the hydrogen into balloons? Or if not balloons, do you know what else would be lightweight enough to float when filled with hydrogen? (I'm not talking on the scale of blimps here, I'm talking anything the size of balloons or only slightly bigger.) 3. I was also wondering how to light them once they're in the air. Would throwing a sparkler do the trick, or would it be better to soak a thin string attached to the balloon in gasoline? Would the fire be out before the string hits the ground? (I could do this well away from any houses or trees, but ideally I'd want to avoid the hassle if it's safe enough.)
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