Recent content by phoneketchup

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    How to set the variation of an integral to 0?

    Thanks a lot! Got the answer!
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    How to set the variation of an integral to 0?

    So I have an integral: ## \delta W=\int_{-\Delta}^\Delta\left[x^2\left(\frac{d\xi}{dx}\right)^2−D_S\xi^2\right]dx ## Here ##\xi## is a function of ##x## and ##D_S## is a constant. ##\Delta## is just some small ##x##. Now I need to set the variation of ##\delta W## to 0. Do do this I...
  3. P

    Integration by substitution for sin/cos products

    Oops! I forgot to put the constant of integration. And yeah I see now.. it was pretty silly haha. Thanks! :)
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    Integration by substitution for sin/cos products

    Ok so I might be doing something silly but I just don't understand what is going on here. So the integral: i = ∫ sin x (cos x)^3 dx First I say u = cos x. So du = - sin x dx. So now I have i = ∫ - u^3 du. Which gives: i = -(1/4)u^4 or -(1/4)(cos x)^4. Easy. But if I say u = sin x...
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    How to Calculate the Output Voltage of a Photodiode?

    Carl, I'm really liking the solar cell you suggested and I may even get it for fun since its so cheap. I sent an e-mail to the company twice to get the spectral response---no reply. Anyway cheers for that! Also for telling me about digikey. You're right Dave I don't think any photodiode would...
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    How to Calculate the Output Voltage of a Photodiode?

    Yeah I was talking about photodiodes but solar cells would work just as well. Basically what I need to do is use a laser(s) to illuminate photodiodes/solar cells and get a constant output voltage of about 5-10V which is the voltage input for an HV module that will give me an output of 2kV which...
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    How to Calculate the Output Voltage of a Photodiode?

    Or is it something like for any given wavelength/intensity (as long as its bright enough and above the threshold wavelength) the output voltage will be very close to the open circuit voltage?
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    How to Calculate the Output Voltage of a Photodiode?

    Do you know how I can calculate the output voltage of the photodiode due to a laser of a given wavelength and power?
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    How to Calculate the Output Voltage of a Photodiode?

    Hello everyone! I'm trying to figure out how to calculate the output voltage of a photodiode in the photovoltaic mode. I want to generate about 5-10V using lasers and a series of photodiodes without using an op-amp (just Vout of the photodiode equvivalent circuit). If I could get any help...
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