Recent content by gtbiyb

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    LCD cell thickness - why is this restricted?

    Hi, I have read loads on LCD operation and in particular NT-LCD and understand the twisting of the light by the LC. Everywhere i read it states that "the thickness of the cell is crucial for correct operation" but does not say why! Why is this? Is it to do with the pitch of the LC helix...
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    How to prove units when you have logs in an equation

    But what do you do then to prove the units in the example i gave, I'm sure my transposition is correct.
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    How to prove units when you have logs in an equation

    Anyone got any advice on this?
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    How to prove units when you have logs in an equation

    I can see the original equation i put down was wrong as i was doing it from memory and it was the general theory i was after! The above is correct though. Matt
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    How to prove units when you have logs in an equation

    Thanks guys, So i have put thought into this in general but in other situations the units cancel as the log is taken of a ratio but in this case i have basically a simultaneous equation: P(z1)=P(0)e(-z1/λ) and P(z2)=P(0)e(-z2/λ) I know P(z1), P(z2), z1 and z2 I want to know P(0) So...
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    How to prove units when you have logs in an equation

    Yeah i see that thanks, i have also just read that in e^x the x has to be dimesionless. But my answer should be a pressure in Pa! I transposed a formula to get that above but am confident its valid.
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    How to prove units when you have logs in an equation

    Hi, What happens when, following a numerical calculation, you have to prove the units but the equation has logs? For example: ln P = (ln z1 - ln z2)/(z1 - z2) So as the RHS will simplify to a number when all values are known you end up with: ln P = x, x being some value so to find P you...
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    Alternator Theory: Questions & Answers

    Thanks for the response, So is it possible to add charge to the same battery from a second, possibly smaller alternator? I am reseaching an energy saving system in a vehicle if your wondering what I am getting at! Also what happens in a car if/when the battery becomes fully charged...
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    Alternator Theory: Questions & Answers

    Hello all! Ive been thinking about car alternators... and have a few questions! Does a car alternator have to be able to supply max power at engine idle speed? My thought being that you could turn on all electrical devices in your car at this speed. I do notice however that when you turn...
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    What is the output speed at 100 rpm arm rotation in an epicyclic gear box?

    Hi, Cant understand this at all, even modeled the set up with lego but still can't fathom it! I can't see how the arm can rotate with locking something. Cheers
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