Recent content by Excalibur1152

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    Sig Figs: Adding Accurate Lengths with Fewer Decimals

    Right. The 'true' value could be anywhere from 5280 to 2*5280 right? (it could actually have been 1 exactly or 1.9999... miles(the case where x=9999 or x=0)) right?EDIT: If the value could be 1.9999, couldn't it also be .0000001 ? So 5280 plus or minus 5280 feet? Either way, the answer should...
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    Sig Figs: Adding Accurate Lengths with Fewer Decimals

    So just to make this clear, if you measure a certain dimension of something (whether it be time or length and so on), the number of decimal places kept can change depending on what units you use? So that 1 micrometer >>conversion>> .000001 meters each has one sig fig, but different numbers of...
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    Sig Figs: Adding Accurate Lengths with Fewer Decimals

    Much thanks, I think I am starting to get it now...but I can't control my mind from trying to think of places where the sig figs system doesn't work. If I am able to articulate anything else, I will post it but I probably won't.
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    Sig Figs: Adding Accurate Lengths with Fewer Decimals

    My point is that if you measured the length of the bar really accurately, and then measured a second one that was a seemingly infinitesimal length compared to the first one such that when you sum them, you can still know the final length to one part in a million (or similar). BUT, because you...
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    Sig Figs: Adding Accurate Lengths with Fewer Decimals

    One thing I have always questioned is this: Teachers always tell us that a final answer should never have any more significant figures than the least number of sig figs on a measured value used. But something doesn't add up here... Suppose you knew the length of a metal rod to be...
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    Gravitational field from earth/ center of mass

    When calculating the gravitational field from the earth, why can we make the assumption that all of the mass of the Earth is 'averaged' at the the geometrical center? If we imagine the Earth as a bunch of pieces, and then calculate the sum of forces from each of these pieces, would it not be...
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    Question about the motion charges moving within an electric field

    Indeed, if the field lines are straight, then the charge should only move along the field lines. If the charge does have mass, it gains kinetic energy, and so when the field line curves, then work has to be done over a distance to "change" the path of motion? Wouldn't this distance be the...
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    Question about the motion charges moving within an electric field

    So if I were to place a (positive) charge on top of one of the field lines ^^^ without giving it an initial velocity, it would never leave the line? It's path would only exist upon the same field line? (I know that there are an infinite # of lines, but as far as the picture is concerned)
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    Question about the motion charges moving within an electric field

    I've almost certain that I have read/ seen from MIT's OCW that the motion of a charge within an electric field does not follow the field lines. Today my physics teacher said the opposite, that the path of motion of a charge within a field will follow a field line. Who is right? And why? EDIT...
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    Epsilon-delta definition of a limit

    True, didn't think of that.
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    Epsilon-delta definition of a limit

    In a limit, the x-value can never equal the x-coordinate of the limit (c). That means that there will always be a distance between x and "c." then: There will always be a distance between y and L.
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