The deformations I want to give are of the order of 5%, so it does not seem large enough to deem a constant volume correction (to me at least since it's so small and other effects may come into play), and it is plastic so Poisson's ratio does not really apply. I have been considering not...
Well, I think I found the main source of the problem as being loss lead connections from the strain gage. The signals seem considerably more stable now. What would you guys recommend for having good connections to a breadboard? Should I dip some solder onto each lead and try to make a permanent...
Hello,
I recently put together a standard (or mostly so ;)) cantilever load cell for some tests I want to do (basically I am making a screw driven tensile machine). The cantilever has two strain gages mounted on it. These strain gages are wired in a half bridge configuration. In addition to...
Hello,
Is using Poisson's ratio to calculate the cross sectional area accurate after a material has been extensively cold worked and deformed. For example say I have a wire at some nominal length and thickness (which is too small for me to precisely measure, but I know at the start). So can...
Hey another quick question, for the power supply voltage, how close to +/-15 volts do I need to be to have the instrument work right? Is it correct that the op amp will work w/ a +/-5 volt to a +/-20 volt supply?
Thanks,
-Scott
Well wouldn't that the changing current from my heating circuit, cause the voltage drop to be different across the material, which would in turn provide a different value than expected for my four-wire kelvin circuit, which is simultaneously hocked up to the material. Perhaps I can use relays...
Hello,
I am making a circuit which runs a large current through a material at intervals, heating it, which then temporarily stops to make a resistance measurement. Each individual circuit is not an issue in itself, nor the timing of it since I have a computer interface which can grab analog...
For the INA101, in the configuration for the most basic circuit with the TO-100 package, two 1 mircofarad capacitors seem to be required to be placed in parallel with the supply voltages. Why is this, and is it actually necessary for an operating circuit, since the circuit example with the Dip...
Ok then... setting up the kelvin connection seems pretty standard w/ the constant current source and all that...but what would be the best way to amplify the voltage drop I get from the second set of connections? If the drop I have is a few millivolts at best, what would be the best way to...
Sorry in advance for not using latex...
So if I have the equation for the gravitational field of a ring, g=G*m*z/(z^2+r^2)^1.5 (where z is the distance to some point along a line perpindicular to the center of the ring, and r is the radius of the ring), what useful thing can I get out of making...
...to do a Taylor series expansion of an expression for the gravitational field? My physics teacher did a it few times on the board, but I do not understand how it gives me more information about the asymptotic behavior than substituting some scaled factor in for r, and then solving the limit as...
I just want to mention also, that though the total magnitude of change is about 1 ohm, I am also looking for the very fine details contained in that range. The solution that my electronics teacher and I came up with to optimize the produced values to the measuring range of 0-5 volts, was to use...
There are a few more conditions that I did not mention before that make it more difficult than that. Firstly the wire itself ideally cannot have a significant amperage (about 0.05 amps or above), because any significant amperage, if passed through the wire for anything but a short time, will...