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    Desperately need help with teeth grinding device

    Was searching for piezoelectric bite pressure sensors, on the theory that a piezo sensor could also be used as a piezo audio alarm with direct bone conduction from the tooth to the ear, but instead found these examples of what's involved in bruxism monitoring...
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    Stator powered LEDs

    The color coding is just for colorful identification of the wires involved. Success depends upon finding an appropriate LED fixture, or making your own for whatever LEDs are available. You might start searching for LEDs here: https://www.superbrightleds.com/cat/led-headlight-bulbs-conversion-kits/
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    Stator powered LEDs

    Looks like one coil of the magneto powers the lights with AC. There is a shunt regulator, likely back-to-back power Zener diodes, to limit the voltage going to the lights. So a 35W bulb @14V is drawing 2.5A. Disconnect one of the HI or LO beam wires going to the bulb, put it through a...
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    Measuring small currents (microamps)

    The LT1179 is a quad device. Are there two separate packages, since IC1 & IC2 are shown as powered by separate sources? In order for this circuit to work correctly both IC1 & IC2 must be powered by the same 9V source. Please verify whether the circuit is actually wired as shown in the diagram.
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    Measuring small currents (microamps)

    For the low μA range I would try a μA-to-mV converter and read the mV with the multimeter. For the converter try a 1KΩ resistor. It will introduce 1 mV of offset into the circuit for every μA, but the circuit might not notice that. For higher currents use a smaller resistor.
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    Norton/Thévenin

    Have never seen so many Norton/Thevenin conversions done in one problem, but there is no theoretical reason why it would not give the correct answer. Just seems like a lot of extra work. I got the same answer in the usual way. Are you sure you have the current going in the right direction? It...
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    Transistor Uses

    The bipolar junction transistor has three recognized operating regions: Active, Saturation, Cutoff. Active Region -- The collector junction is reverse-biased and the emitter junction is forward-biased. Saturation Region -- Both the collector and emitter junctions are forward-biased. Cutoff...
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    What is TINC Resistor?

    TiNC is titanium carbonitride thin film. See this German patent application: http://www.google.com/patents/DE3512354A1?cl=en
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    How long would it take the capacitor in the given circuit to completely discharge?

    If the problem statement said nothing about how long the switch has been in position #1, then all you can do is assume it has been long enough for the capacitor to become fully charged. (hevans1944 asked what minimum time was long enough) But you should not try to over-think the solution. My...
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    what is the voltage across C1?

    Correct, but there is no need to calculate the charge Q. Just recognize that the charge is equal in both capacitors. C=Q/V, Q1=Q2, C1∙V1=C2∙V2. The voltage law gives V1+V2=18. So just solve these two equations for V1: C1∙V1=C2∙V2 & V1+V2=18 V2=(C1/C2)V1, (1+C1/C2)V1=18, V1=18/(1+4.7/3.3) = 7.425
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    Python programming course help

    Is there any reason why you can't apply the amortization annuity formula? http://en.wikipedia.org/wiki/Amortization_calculator
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    How long would it take the capacitor in the given circuit to completely discharge?

    It is just a question about how long the switch has been in position #1. Has it been long enough for the capacitor to become fully charged? Is that question not relevant to the problem? What is the purpose of R1 if it is not relevant to the problem? Or is it a trick question where you are...
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    How long would it take the capacitor in the given circuit to completely discharge?

    What is the general exponential equation for capacitor discharge?
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    What is the power dissipated by R2, R4, and R6?

    That method will certainly give a correct answer. However, what is commonly done in this type of situation is to iteratively combine parallel resistances to ultimately find the total source current, then iteratively use current division to find the current in each branch. But if you have a...
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    Exchanging data variables?

    I had never programmed python before but wanted to see an implementation done with nested loops, just because of belief that I/O and calculations should be kept separated, although you seem to have combined them with finesse. Anyway, consider this an example of an alternative approach. It...
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    Exchanging data variables?

    I suspect that the previous problem of printing with string formatting was due to using single quotes instead of double quotes. print "Is your secret number %d?" % guess
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    Lift 1 kg weight using wind power from a fan

    Is it a correct assumption that the fan will be just a small table fan? In that case the wind turbine will be low power and the motor will be even lower power. So the motor will need a gearbox to increase the torque. Is the mass on wheels, or does the motor need to overcome sliding friction...
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    what is bleeder current? n how to find it out?

    Find the voltage across RL from the voltage divider between R1 and {R2 in parallel with RL}, then use that voltage to get the current through R2.
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    Exchanging data variables?

    The issue is that the code needs to show the current guess immediately following a rejection of the last user input. Can't see a quick fix except for a revamping of the control structure. This is an example of why it is a bad idea to perform data calculations within an I/O routine. I'd be...
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    what is bleeder current? n how to find it out?

    It would seem that whoever calculated the answer of 1.96 mA was using a different definition. Was the question to find the bleeder current, or find the current through the bleeder resistor?
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