Foam insulation board in 4'x8' sheets is very easy to bend I tested it with, 1", 2", 3" bend it produces a hot spot too warm to put your hand if board is bent too much. 130°f is plenty warm no one will get hurt. I was aiming at a sliding glass patio door. Sun is in the south you can only do...
Don't use convex mirror you will catch something on fire.
Summer sun is about 420 btu per sq ft. Winter sun is about 200 btu per sq ft. A mirror 2'x3' = 6x420=2500 btu of heat. If your aiming at a patio glass door 5'x6' buy a sheet of foam insulation that has aluminum foil on 1 side this...
1961 My father worked for a well drilling company called, Schlumberger in Lansing MI. One day he told me the company has a radioactive piece of metal that glows white hot all the time we keep it in a cement box in the ground inside a metal box with a lid. Sunday Schlumberger was closed and no...
Information online claims sun is 200 btu per sq ft in winter only when sun is perpendicular to plastic or glass of a green house. When sun hits glass or plastic at an angle there are losses. The steeper the angle the more losses will be.
Is it possible to calculate how warm a green house will...
If you want to own your own business then you will need, accounting, finance, marketing, management courses. If you work for someone else you can take those classes later if needed. If your the boss you hire people to do, accounting, marketing, etc but its also good to know how to do those...
It would be great if we all had a crystal ball to tell our future but we don't. 1 of my college professors used to say, take a wide variety of classes and get a wide variety of experience because no one knows where they will be in 5 years or 10 or 20 or 30 years.
The thing that helped me the...
The original problem is, -3²= ?
There is no way to put parentheses in my calculators. I put -3 in both calculators then push the square button and the answer on both calculators is -3²=9
Everyone adds parentheses to this for some reason claiming it needs parentheses.
I asked the wrong...
I have been out of college 50 years. If you don't use it you loose it. I have forgotten about 90% of what I once knew, maybe more. I took every math class the college had expect, imaginary numbers. I know -x-=+ and 3²=9 and -3² should =9 also. When people add -1 to -3² I have no clue what...
My calculator shows -3² = 9
My calculator also shows 3²=9
Both make sense because -x-=+
-x-=- makes no sense.
I only know real math symbols, what are ^ & * mean?
I makes no sense to pull a -1 out of the air and put it into a problem that has no -1 in it?
-3² should = -3 x -3 = 9
I was reading a NASA web side where I can find angle of the sun and day length at my zip code. Longest day of the year is June 21 for 2 years then June 22 for 2 years, after leap year, longest day is June 21 again for 2 years. I already knew that. Then I see something I never saw before. If...
I'm not sure I asked the correct question. I am trying to learn when our sun is at solar 12 noon on my yard, does the sun light travel a perfect path across earth, 50% before solar 12 noon and 50% after solar 12 noon.
I built a large sun dial in my yard 3 ft tall 6 ft long. I used a compass...
Most of the used electric motors have gears on the shaft. Buy a matching gear 20 to 1 ratio from Browning or Boston Gear. Put the large gear on your wind mill blade. If wind mill turns 100 rpms generator will run 2000 rpms. Wind mill blade rpm and average wind speed where you live will...