How to power a light bulb with an alternator and a bicycle?

I want to power a light bulb with a bicycle for an art project. I don't care much for the science behind it, I just want the easiest way to connect the light to the alternator without having a battery ect... The alternator is an old 4 wire that I pulled from a truck. Is what I am doing possible?

Answer: 
It's possible, but not if you want to skip all of the science. You need to figure out how to make the alternator spin from the bicycle. Alternators have to spin at a high rate. This may involve belts and pulleys. Then you need the proper voltage and wattage light bulb. All of this involves science.

How to make the verification on the kjeldahl method and kjeldahl equipment?

Hy, I want to know how you make the verification on the kjeldahl method and kjeldahl equipment, so that I know for sure, that the digestion unit extract all nitrogen (azot) from the sample. Thx.

Answer: 
Ah, the Kjeldahl Method used to determine the amount of crude protien on any given sample. I used to do this everyday in the place where I had my practicum. Actually, this is my forte. Oh men, that brings back memories... Anyways, there really is no verification needed in the Kjeldahl Method. The only thing you have to be sure is if you have the correct concentrations of the solutions needed in the titration part of the Kjeldahl Method. So long as you followed faithfully the methods involved in the kjeldahl method. But there is one thing though. For every batch of sample that I need to test for protein content, there is this thing we call a "blank sample". Its like this, the digester we have can digest 6 samples at the same time that are contained in this big test tubes. We digest the samples in those big test tubes and those test tubes go in the digester. Of those 6 test tubes, I will only put samples on 5 of those test tubes, leaving one without a sample. But all 6 test tubes will have the same amount of concentrated sulfuric acid & selenium catalyst, including the empty test tube. All six, including the one without a sample, will be tested for nitrogen content. The % nitrogen content of the blank sample will be deducted to each of the 5 samples tested. Then the multiplying with the factors of 6.25 or whatever applies will be used to determine the % crude protein content.

How to wire potentiometer to amplifier circuit board?

I have a 3 prong potentiometer (Ground, input, output) that I am trying to wire into a amplifier circuit board however the board only has Ground and VDD, so I am sort a connection.

I am new to all of this, but just trying to figure out how to get my volume control to work with this amplifier.

Answer: 
The Potentiometer doesn't have "GND, IN & OUT " it has three connections to a basic resistor and you are going to need to get some detailed technical info about that amplifier or you are not going to be able to get this done at all - there are factors like how many ohms the potentiometer happens to be. ( etc... ) and you are gong to NEED to get the details right or this will simply NOT work. GOOD LUCK

How to use My Mechanical Engineering degree in the Medical Field?

I have a MS in Mechanical Engineering with a year of experience in the Bio-Fuel Field. I grew up wanting to become a doctor, but somewhere down the line became an engineer instead. How can I use my Mechanical Engineering degree to cross the gap and help people in the medical field?

Answer: 
There are many areas where ME is needed for building medical devices. The radiation oncology industry build big mechanical machines to house and manipulate the radiation beam. They build 7-10 ton machines that move with the precision of less than 1 mm that is required for accurate treatment. Another uses a robotic arm with a small medical linear accelerator to treat tumors with 100's of shot. Intuitive Surgical makes the da Vinci robotic surgical system that allows physicians to do more precise surgeries. On a smaller scale, ME are always needed to build/mount devices with special requirements that needed someone with an understanding of mechanics and materials to build the a device that a doctor dreams of. ME as also find their way into industrial design to make devices more usable and attractive, e.g. CT machines, better pill bottles, Pyxis drug dispensing systems. Nanotech is also a new frontier with applications to medicine. Maybe your experience in biofuels may be useful in research universities that are trying to create self assembling systems to mass produce medicines. At UCLA (I think) there is research to build in-field use portable one time use diagnostics systems that can do a battery of tests w/o have to visit a laboratory. ME are needed to build cheap microscopes and other equipment for use in the third world. Check job descriptions in the Bay Area (craigslist or linkedin or other) or Boston (MIT, Harvard). Check with research universities with medical schools in your area. Look at what kind of research they do and do an informational interview with some of the researchers. Read Science Now, Sci-Am, etc.... The world is your oyster. Best of Luck.

How to calculate the arrow speed of a bow with just knowing the draw length and draw weight?

For example if my crossbow has a draw weight of 200 lbs and a draw length of 15,5" and my arrow weight is 350 grains what will my arrow speed be?

Answer: 
I need to know the weight of the arrow in lbs. Never heard of grains which I suppose must be some specialist unit! Of course I can search what grains are but it's your problem so why should I do the donkey work?. Have the decency to inform of that and I'll get you the answer. Saying please would also elevate your charm from its present level at more or less rock bottom!

How to get the internal energy when given only the pressure and temperature?

Using the steam tables I have to calculate the internal energy u in Btu/lb, when given the Ammonia at p=35lbf/in^2 and T= 0 degrees F.

Answer: 
1] Steam tables will not help with NH3.... 2] U = H - PV in case your table gives H only 3] See the following [rather long] link for NIST data http://webbook.nist.gov/cgi/fluid.cgi?TLow=0&THigh=10&TInc=5&Digits=5&ID=C7664417&Action=Load&Type=SatP&TUnit=F&PUnit=psia&DUnit=lbm%2Fft3&HUnit=Btu%2Flbm&WUnit=ft%2Fs&VisUnit=lbm%2Fft*s&STUnit=lb%2Fft&RefState=DEF

How to make a sheet of paper hold a pile of books?

So the challenge is to make a structure out of a single sheet of construction paper that will support a pile of books (guessing up to 7 lbs maybe?). You get a one sheet of paper and do whatever you want with it, it must be 3 inches high, and whichever can hold the most books will win. Any ideas? My only two ideas are to cut the paper up and roll it into a thick cone or some how make a really thick box but not sure if either will work.

Answer: 
No. Fold it in halfway until 3" high and make it into a circle.. Attach the ends somehow and that sucker holds forever:

How to calculate the range of current given the tolerance of resistors?

given 5.6k, 6.8k, 10k with 5%tolerance resistors in parallel with a 24V power supply, how do i calculate the range of current?

Answer: 
Calculate the equivalent resistance of the parallel combination. That comes out to be 2.35k. Now tolerance is always added, therefore the total tolerance becomes 15%. Now equivalent resistance becomes 2.35k+-15%. Calculate the current range within these limits. That comes out to be 8.89mA to 12mA.

How to calculate thermal expansion of a hole drilled in a steel bar?

I'm drilling a hole to the core of a 10" steel bar to put a thermocouple in and gather data to make a cooling curve. My question is, how do I know how much bigger to make the hole so that the thermocouple can be inserted when the stock is at temperature, roughly 2300*F?
Am I over thinking this? Would the hole expand and contract at the same rate as the rest of the bar therefore always staying the same size relative to the total bar size?

Answer: 
u can answer this question using a finite element program. u have to know the location of the hole, the size of the thermocouple and the size of the steel bar... 10"x.000012"=.00012".......u're over worry. just drill the hole 1/8" bigger than the diameter of the thermocouple.. but then steel melts at 1200 degree celius and that's 2192 degree F.....even the thermocouple would melt....

How to become good at Operation Research/mathematical modeling?

I have an Operation Research class, mathematical Modeling. I spend alot of time on it still no good result. I am not that much dumb but it does not work. Any one can share their experience.

Answer: 
Models are suppose to be simpler then reality. One model that was suppose to model the entire earth had only 7 variables. Is there anything you can toss out of your model? Even if only for a short while, until you get at least part of simulation giving a good result. Then add back if you have to. Sometimes you can condense two variables into one. Especially if the data follow the same or similar curve. Like when the folks at the recycle plant make all their trash cans weigh 6 pounds and set the scale zero at minus 6 lbs.

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