# EdEarl

Senior Members

3454

1. ## Electromagnetic Circuits

If you have time before you must turn in your paper, try the following experiment and consider adding a description of your experiment to the paper. You will need: A magnet of any size. Some iron filings. A sheet of cardboard or stiff plastic. Place the magnet beneath the sheet. Sprinkle the iron filings on top of the sheet, and gently tap or shake the sheet to distribute the iron filings. Note the pattern. Take a picture and include it with your paper. You can make a substitute for iron filings by using some steel wool (the grey stuff that is really fine, as thin or thinner than hair). Use scissors to cut the steel (iron) wool into very small pieces. Use these tiny, tiny pieces instead of iron filings. You might find a video of this experiment on youtube. The pattern of filings you see on the sheet is formed by magnetic flux lines. These lines are created and tuned off by electricity in an electromagnet. You can make a transformer, if you can get a big nail and some very thin wire, 25 feet would be enough. Home Depot will have what you need. To demonstrate it works you will also need a D or C cell (battery) and some really cheap head phones that you can ruin (cut off the plug to expose the wires).

3. ## Sub-millimetre drilling ?

Water jets and lasers are used to cut things, but I don't know what they use for submillimeter work.
4. ## Artificial Intelligence

I am not an expert, but have studied artificial intelligence (AI) and artificial general intelligence (AGI). I think your concerns are valid, but the state of the art is far from being able to realize a system that would fit your description. Moreover, I believe scientists are also concerned about similar issues. In my opinion making emotions in a computer will be difficult and not relevant to making AGI help with science. There already exist hundreds or thousands of AI systems that analyze handwriting, read printed documents, translate speech into text, play chess, play Jeopardy, etc. These systems do what they are designed to do, and do not exhibit any spontaneous emotion, and there are good reasons why they cannot. Our emotions are associated with hormones and neurotransmitters such as dopamine, noradrenaline, serotonin, oxytocin, cortisol and GABA. Computers do not have such chemicals. It might be possible to simulate the effects of those chemicals, but that would take extra computer power, which would reduce the effectiveness of AI programs. Thus, adding emotions to AI programs would be difficult and unwise. It is hard enough to code AI programs already without adding emotions to the coding burden.
5. ## Electromagnetic Circuits

I found a paper, see below, that requires an understanding of calculus. It would take me a day or two to read and understand it. http://arxiv.org/pdf/0805.1079.pdf A transformer is about as simple an electromagnetic circuit as possible. I'm not going to do your homework, but whatever you write I will review. And, I will answer questions. How much math do you know? How much do you know about electromagnetism, any equations? What is magnetic flux? I am online quite a lot, so you should be able to ask many questions each day.
6. ## Series parallel combination cicuit

The short circuit essentially removes R3.
7. ## Series parallel combination cicuit

Correct. There is a short circuit across R3.
8. ## Reasons not to worry (Climate change debate)

I cannot afford most peer reviewed papers, but some reliable sources are available. Here are a few I believe are reliable. http://nsidc.org/arcticseaicenews/ http://phys.org/news4906.html http://www.nasa.gov/topics/earth/features/glacier-sea-rise.html http://nrmsc.usgs.gov/research/climate_glaciers.htm
9. ## Reasons not to worry (Climate change debate)

I didn't mean to imply government would not be involved, merely that business will shape laws. Reinventing fire doesn't discuss all the things I have learned about climate change and related issues. There is no doubt considerably more going on that I know about. And, research will yield additional relevant information and advanced technology.
10. ## Reasons not to worry (Climate change debate)

True, correlation is not causation, but without other proof, there is a 50% chance. Since we can create jobs and maintain or improve our economy at the same time we reduce anthropomorphic CO2, it is better to play it safe and reduce CO2. Subsequently, after CO2 reduction, we may better understand the effect of atmospheric CO2 and temperature.
11. ## Reasons not to worry (Climate change debate)

It is obvious that burning fossil fuels puts CO2 in the atmosphere, and from ice cores that global temperature is linked closely to CO2 levels. Reducing CO2 levels is a worthy goal. However, IMO doing so will not destroy the economy; on the contrary, it is and will continue to revitalize the US economy because we will not be spending billions to buy foreign oil, and these industries will and are creating US jobs. I just read the a 500MW solar power plant in San Antonio, TX created 800 jobs and saved the local power company money compared to them continuing to use an existing coal power plant. On the other hand, there are scenarios whereby the eliminating fossil fuels would be an economic disaster. But, industry will not do that, and they control enough governmental decisions I have no fear the economy will not get into trouble from the conversion. On the other hand, doing nothing to control CO2 in the atmosphere would cause a disaster. Mountain glaciers around the world are disappearing. If they do, many of the worlds major rivers will be dry except when it rains, and millions or billions of people will die. Eliminating CO2 is and will continue to be a balancing act. We need to grow economies and preserve critical natural resources at the same time. It is complicated and cannot be done immediately. Some people clamor for too much too soon, and others want to go too slow. I hope we progress fast enough but not too fast.
12. ## Determing flow direction of a river

It is a contour map. In other words, many of the lines on the map indicate constant altitude along the line. Dotted parallel lines are probably a road or railroad. My eyes cannot make out all the detail. It is difficult to explain here, but sets of curved lines show hills or mountains and valleys, The river (blue) is in a valley and brown lines beside the river (e.g., left-bottom just above the bend) show a steep rise in altitude, because the brow lines are close together. A small loop in these lines shows the top of a hill (or a depression). The altitude is marked in numerals (e.g., 800) and there will be other altitude numbers on lines to show altitude increasing or decreasing from contour line to contour line. If you count ten lines between 800 and 700, then each line is 10 (feet/meters) difference in altitude from the others. Refer to the legend on the map. As water flows down hill, you must determine which way is downhill. I hope this helps. I apologize if my explanation is difficult to understand.
13. ## Richard Dawkins Documentary - Enemies of Reason

He is rather famous or notorious, depending on your point of view.
14. ## Ancient Technology, Camera Obscura And Greek Computer

Since there are more people on the world today, there are probably more people with the intellect equal to people like Plato and others from the past. Since evolution continues there may be people even more capable. Nonetheless, the contribution to knowledge, art, music, and literature by historic figures is notable. We would not be where we are without them. We owe them honor and respect.
15. ## Reasons not to worry (Climate change debate)

Yes, climate has always changed. We are a part of nature, and we contribute to the change. The only question, is how much we contribute, and whether our contribution is contrary to our needs or not.
16. ## Why does motion exist in this universe?

Science cannot answer the metaphysical why, such as why is there a universe or why is there motion. Science does answer the physical why as the Universe began with a big bang and everything was thrown into motion. Moreover, dark energy (whatever that is) pushes on the fabric of space time causing acceleration of distant things away from each other, and forces (such as gravity, electrostatic, weak and strong) suck pulling things toward each other. And, for some unknown reason photons move at the speed of light. I don't know if other things, such as neutrinos, move at the speed of light or not. I do not remember the details, but two other kinds of energy affected the expansion of space-time, one caused inflation very early in the history of the universe, and another energy was dominant after inflation and before dark energy is dominant.
17. ## Tornado May 20, 2013 Moore, OK

Tornadoes create terror and destruction. I have been lucky, not having been in one. I remember as a child having tornado drills in school. An a few years ago, a tornado came through my town, about a mile from me...a much smaller one. Nonetheless, it left a path of destruction. Please accept my sympathy and hope that everyone injured makes a full recovery, including those who survived the ordeal without a scratch, but were terrified. And, I offer condolences to those who lost friends and family members.
18. ## Electronic Score Keeping Solution Needed

Add a pressure sensor to indicate when something actually touched the target.
19. ## Electronic Score Keeping Solution Needed

A webcam in or near the target can see the ball touch or enter the target. A computer program can monitor the camera and detect a score.
20. ## Reasons not to worry (Climate change debate)

About 10,000 years ago, glaciers covered New York City, and many other places. This year, for the first time in recorded history, it was warm enough for the Greenland ice cap to melt enough for a thin layer of water to cover it everywhere. Glacier National Park is almost glacier free because they have been melting for a very long time. In fact, most mountain glaciers in the world are receding, in other words melting in the summer faster than they are being replenished in the winter. Permafrost in Alaska is melting, in other words it is no longer permafrost. The evidence for global warming is pervasive, and obvious. Yet, some people who live in parts of the world where there is no obvious evidence, deny the evidence exists. Get up from your couch and visit somewhere like Tuvalu, the headwaters of the Ganges, Greenland, or Alaska and talk to people who are experiencing global warming. If such an experience does not convince you that global warming is real, then you will have convinced me that humanity is self destructive.
21. ## Any way to induce hallucination without drugs?

It may be possible to train yourself to hallucinate. The same neurons activate when we remember or think about something as when we experience it. We can improve our strength by thinking about exercising. Thus, reading a fantasy story must be similar to hallucinating. Reread the story until you memorize it. Replay the memory until it seems real...maybe.
22. ## Shape of Universe

My feeble brain is befuddled by the idea of infinity and gods. Just because I can consider whether a god or gods exist neither confirms nor denies their existence. Just because I can think of doubling an infinite set of integers, does not confirm that the set of infinite numbers actually doubled or not. Do alternate universes branch off from ours as we encounter alternatives in our lives. Do numbers only exist when someone thinks of them or do they always exist. How many angles can dance on the head of a pin? Forgive my babble, I think I'll move on to a subject that is easier to resolve...maybe climate change.
23. ## Fire with ordinary things i.e. from ordinary air or anything

Unusual: Steel (iron actually) wool burns (not the stainless steel stuff); rather, the kind that is gray and very fine.

25. ## Reasons not to worry (Climate change debate)

Sometimes I wonder if some people have a lemming gene that makes the suicidal or irrational during times in the face of prolonged stress.
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