# Externet

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1. ## Volts, Amps, Ohms, and Capacitors!

Hello xeluc. ...."I understand everything you said; You said a 1 Farad capacitor charged with 9 volts can discharge 1 Ampere in 9 seconds or 9 Amperes in 1 second. How would you pick which one you wanted ot happen, a resistor?" --------> Yes, the resistor . But your wording should say {Charged TO 9 Volts, not WITH} A 1 Farad capacitor charged to 1 Volt would have: 1 F x 1 V = 1 Coulomb. If the wires discharging it have 1 Ohm resistance: 1 V ÷ 1 Ohm = 1 Ampere and the time to discharge is 1 Coulomb ÷ 1 Ampere = 1 second The other case, with the voltage being 9 Volts: 9 V ÷ 1 Ohm = 9 Amperes and the time to discharge is 9 Coulombs ÷ 9 Amperes = 1 second Or; if you increase the resistance of the discharging wires With the resistance being 9 Ohm instead of 1 Ohm, 9 Volts ÷ 9 Ohms = 1 Ampere The discharge time is : 9 Coulombs ÷ 1 Ampere = 9 second [if you increase the resistance, the current will discharge in a longer time] Remember: Coulombs ÷ seconds = Amperes = Volts ÷ Ohms And imagine a swimming pool (large CAPACITY capacitor) filled with 2 inches of water (~2 Volts) and a frying pan (small capacity capacitor) filled also with 2 inches of water (same ~2 Volts) The time needed to empty each trough equal drain pipe size (resistor) will be different. Changing the size of the drain pipe (resistor) will change the draining times. The water depth is the voltage; the size of the container is the capacitor capacity, the restriction by the drain is the resistance. I want to correct MY mistake in post #20 above. Where says " Energy in Joules = voltage x capacity " Should say "Energy in Joules = voltage x charge" Miguel

3. ## problems with RF modulator, help?

Hi. Use a VCR. Connect your camera signals to video and audio inputs, and feed your TV ANT IN from the RF OUT threaded connector. If you know some electronics, you could canibalize the modulator inside a discarded VCR. It is the tin box inside it that has the RF OUT connector attached to it and a channel 3/4 selector on it. It will; need about 8 to 12V to energize it. Miguel
4. ## Concentrating heat?

If I understand your question, to concentrate HEAT, you must have a larger MASS holding the heat If you want to raise/concentrate TEMPERATURE, a focusing array of mirrors could do it. If the heating element in the chamber is an electric resistor, a parabolic/eliptic mirror behind it will concentrate the temperature to a focal point. Miguel
5. ## Hall Effect held Capacitor?

As expressed above, you are lost in space about what a capacitor is and how it works. After charged, as there is no current, there is no magnetic field. There is only electric field. If you want to do your experiment, buy a vacuum capacitor and stick a magnet outside. Then you will have a magnetic field between the plates. Miguel
6. ## Volts, Amps, Ohms, and Capacitors!

....."First off, I need clarification on some things. I know what an amp is. It's how fast the current is moving. Great. ------> WRONG. First, it is not amp. It is Ampere, and second, is the amount of electrons flowing per second. EXACTLY as water flowing in a pipe at a constant velocity. Now Voltage. I know the literal definition. It states that Voltage is the Potenital difference of charges or something ot that effect. --------> your "something ot that effect" Is like the PRESSURE on a water pipe. What I may or may not understand is it's relationship with Amperage. --------> More Volts, -> more Amperes. As if the water has more pressure, more amount of water will flow. The rest of your post is a salad of confusion, set it aside until you understand the concepts clearly, and then we can continue ONE question at a time I know that you can convert high voltage low amperage currents to low voltage high amperage currents, but I don't understand how voltage is measured. It's easy to understand that current moves faster in higher amperage currents so that means high amperage can kill you easily. thing is, If I have a high and low voltage of the same amperage going throuh me, what would be the difference. I realize that the higher voltage could be converted to a higher amperage, then again so coudl the lwoer voltage. So like I said, whats the relationship here, other than jsut sayuing voltage is lie kthe pressure in a water pipe. that doesnt hlep. What difference does a high and low voltage have when both currents have the same amperage? So that's that. Now we go to resistance. I understand the equation I=V/R . It's all good. Here's what I dont get. If you have a current thats 9 volts flowing at 1 amp, the resistance would be 9 Ohms, correct? That would satisfy the above equation, but then you have to deal with the resistance of the wire the current is traveling through. I understand that the resistance would be higher (since the equation could be re-arranged as IR=V) so wouldn't the voltage continually rise as it flowed through the wire? I know it doesn't SEEM correct, but that's what the equation states. Of course some power would be lost due to heat from the resistance, but I'm not sure if that's relevant. So here comes my last 2 questions. Sorry again. If I have 2 capacitors; one the size of a marble and the other the size of a 2-liter bottle, and they were both charges at 1.5 Volts; What would happen? Would they both be charged at 1.5 votls and the bigger capacitor have a larger amperage? --------> The charge on a capacitor is not Volts nor Amperes, it is Coulombs, equal to Volts times Farads. Would they both have the same amperage and the bigger capacitor have a larger voltage? Would the larger capacitor have a larger amperage AND voltage? If so, what determines the ratio of power between voltage and amperage. So thats one quesiton ; here is the last one. If I have 9 volts flowing at 1 amp from a capacitor, and in the "circuit" is a mor eresistive material, like graphite; would that raise the voltage since resistance was added? That ties in with a previous question I guess.. So thats everything I'd lie kto know. I'm sorry if all this has been answered, i looked around for a little while.. And I'm sorry that this was very long also. SAo thanks in advance for anyone who helps me!
7. ## Help! - Project Ideas

Hi. Just develop an experiment to measure the propagation speed of gravity.
8. ## Settle an argument please....

To make things harder, I don't think so ! A water balloon, and a plain air balloon, both identical and inflated to the exact same size, will be affected by the same air drag resistance, and will have different weights. For very sure, launch both from your Empire State building, and you will find that a long time after that pedestrian dries out, the air inflated one is still flying. Even if you do it in your bedroom with zero crosswind, they will not fall at the same speed. It's the law of selective gravity. Miguel
9. ## Which nearly pure minerals are more abundant ?

Thanks, gentlemen. From the responses above, the list of reasonably pure abundant natural soils could be: Lime Chalk Salt Coal Silica Water Silicates of calcium Silicates of aluminum Silicates of magnesium Silicates of iron Sulfates of calcium Sulfates of barium Sulfates of strontium Chlorides of calcium Chlorides of sodium Chlorides of potassium Chlorides of ammonium Calcium fluoride Nitrate of ammonium Nitrate of potassium Now, here is where you, skilled guys, come to play: Using any of the above, or more than one, plus heat plus any other requiered compound if needed, what mineral fuel can you come up with ? Example: Coal + lime + heat = calcium carbide -yields acetylene fuel- Let's get rid of petroleum, yes ? Miguel
10. ## Which nearly pure minerals are more abundant ?

Which soils are abundant in somewhat pure form in nature ? Like lime, chalk, sand, what others ?
11. ## Razor sharp leading edges...

Hi. Which drag coefficient is greater; a rounded leading edge or a razor sharp leading edge for a given wing/keel ?
12. ## What is the force ?

NO. Homework was 30 years ago.
13. ## What is the force ?

Hi. What is the force exerted on a 1m² vertical plate held transversal submerged in a river flowing laminar at 0.5m/s ?
14. ## Would someone please calculate... ?

Perhaps was improperly expressed... Would the words WATER WHEEL make more sense than paddle wheel? Miguel
15. ## Blocking sounds

Hi. Install an audio amplifier with the speaker aimed to the neighbor. The hard part is to locate a microphone in such a way that will not pick the speaker output but will pick the neighbors conversation (or noise). Then you will be blasting them with their own noise. In a short while, they will close the door. It depends much of the particularities of the building, windows, layout, etc. Miguel
16. ## Bell's Theorem

Searching with ...Google ? ... Wikiwhat ? ... NAH ! http://www.scirus.com/srsapp/searchq=bell27s+theorem&ds=jnl&ds=nom&ds=web&g=s&t=all This is complete------>http://www.scirus.com/srsapp/search?q=bell%27s+theorem&ds=jnl&ds=nom&ds=web&g=s&t=all<----- (copy and paste) Miguel
17. ## idea

Oh, yes, easy ! Wear this as a hat: http://www.jerry-howell.com/Miser.html http://www.nmri.go.jp/eng/khirata/stirling/kiriki/models/plm_top.html http://www.stirlingengine.co.uk/ and attach a tiny generator to it. Miguel
18. ## Vent pipes...

Hello. The flow of a fluid in pipes improves by the use of venting pipes, placed at certain points, as those shown over the roofs in dwellings. They really do work aiding flow. They are not something just to get fumes out. My fluids mechanics text books from the university never mentioned a word about them. Maybe I had the wrong books, but the thing is I never understood the principles of their use, their preferred locations, the effect of their lenghts and diameters. Can anyone explain how they work and why ? Thanks, Miguel
19. ## Would someone please calculate... ?

Hi. Yes, disregarding friction. Now the no load part cannot understand... If there is no load considered, then there is no power ¿? Am unsure if I calculated this 30 years ago with a result of 50HP, I may be confused. I do not remember well if the diameter of the wheel calculated irrelevant, but I think so. The point is knowing the capability of such 1m² paddle wheel to replace a current diesel engine used for pumping water from the same river for irrigation. If the result is not enough, then increasing the area of the paddles to be built. Miguel
20. ## Would someone please calculate... ?

Hi. Unable to rescue by books at the moment, and several decades after the university years, cannot remember enough to calculate this : A paddle wheel with 1m² paddles (1m x 1m) is turned by a river flowing at 0.5 m/sec. What is the horsepower generated? -The paddle wheel is attached to a pier, the paddles submerge fully when at the low point.- Or, if someone can lend me the formulas, thanks! Miguel
21. ## Tanning hides process ?

Hello. Nothing to do with skins under bikinis, nor the sun is involved... How does it work? Can an animal hide be processed at home? What chemicals are involved and what goes on the process ? Thanks, Miguel
22. ## Emitting materials...

Hi. What harmless material attached to a moving object or animal, could be useable for tracking by detecting its emission of particles, waves, radiation or anything from the largest possible distance by modern sensing technology, without being electronic at all ? Sort of some tracer to locate/find which in thousands of packages or vehicles passing by carries such material inside ? Like the body heat detection used from aircraft while searching for lost persons in a forest, but not being obstructed by common materials, trees, buildings, and producing a recognizable signature. Miguel
23. ## Natural Metals unOxidised?

This black sand at a Pacific seashore (not on fresh water rivers) is highly abundant, but has never been tied with precious metals. But its titanium content is large, as heard from knowledgeable people. A good way to magnetically pick soils is by putting the magnets at the bottom of a plastic bag, and removing the bag to collect, the material falls off leaving the magnet clean. Surprisingly, if you look closely with magnifier, many transparent grains of sand are equally attracted by the magnet. Don't know if differs from the black sand composition found on gold bearing areas. Miguel
24. ## Natural Metals unOxidised?

Can you discern if the black sand picked is not Ti binding with Fe? It's one of those things heard as a kid; the local portland cement factory uses black sand collected from beaches as part of the recipe to improve the clinker. Miguel
25. ## Inorganic alcohols

Hi. As I know nothing in the subject, am asking if isopropyl is inorganic, and which other alcohols are produced from inorganic chemicals not derived from petroleum. Thanks, Miguel
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