Recent content by Derrick Palmiter

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    Sig figs/certainty in percent error calculation

    Can anyone recommend a good text/reading material that explains this concept in a bit more detail than a standard high school physics/chemistry textbook would? Many thanks to all involved for your assistance.
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    Sig figs/certainty in percent error calculation

    And that precision is relative to? The precision of the original measurement which is to the hundredths place? Is that your meaning? That the precision of the result is of equal degree as the precision of the measurement?
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    Sig figs/certainty in percent error calculation

    Please help me understand how this applies to this situation, for both the initial subtraction of 1.95-1.87 and the subsequent division by 1.95.
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    Sig figs/certainty in percent error calculation

    Hello, all. Quick question about how to apply sig figs in percent error problems. Eg. If the actual/target value is 1.95 g and we measure 1.87 g, then should the percent error of our measurement be reported as 4.10% or 4%? Normally, at least abstracting from the problem, after subtracting...
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    I Domain of the identity function after inverse composition

    Thank you very much. The precalculus book I'm using doesn't explain this question of the composition of domains very clearly. So, just to make sure I understand, the domain of f ° g in my example would be (0,1] and of g ° f would be [0, ∞). (I know that's how you prefaced your explanation...
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    I Domain of the identity function after inverse composition

    Hi, I'm struggling to understand something. Does domain restriction work the same way for composition of inverse functions as it does for other composite functions? I would assume it does, but the end result seems counter-intuitive. For example: If I have the function f(x) = 1/(1+x), with...
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    Sig figs - How strict to be as a grader?

    It's a half point for sig figs /units, or any other info that might be needed. So, it's a quarter of a point for each taken individually. Sorry if that was unclear.
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    Sig figs - How strict to be as a grader?

    My practice has been to deduct approximately 5% of the point value for the problem. So if the problem is 5 pts, I usually award 3 for correct set-up, and 1.5 for accurate calculations and half a point for significant digits/units/etc.
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    Sig figs - How strict to be as a grader?

    Sure, here it is: A man is pushing a 150.0 kg desk across a floor. The frictional coefficients between the desk and the floor are μs = 0.45 and μk = 0.35. If the desk is already moving, how much force must the man exert to keep the desk accelerating at 0.30 m/sec2? The textbook's rules for...
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    Sig figs - How strict to be as a grader?

    Yes, that's just it. Exactly the type of issue I'm dealing with, except in a multi-step physics problem, the intermediate answer can be off by quite a bit more than just a tenth. Today in class we looked at a Force vector problem or two involving friction, where, depending on where the...
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    Sig figs - How strict to be as a grader?

    Thank you to all for your insightful responses. I've read several of your recommendations in other places, but was not sure how prevalently held these opinions were. Saving the rounding for the end result makes good sense to me. I'd like to thank Vela, especially, for pointing out, that for...
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    Sig figs - How strict to be as a grader?

    Thank you for the response. I'm teaching junior and senior level high school physics. I'm not really aware quite what my peer expectations would be, hence, my posting here. I'm trying to educate myself on what may typically be expected by other high school science teachers. In general, I...
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    Sig figs - How strict to be as a grader?

    I'm in my first year teaching Physics. My students all understand the importance of significant digits and the rules for applying them, but in some more complicated calculations, like multi-step vector component problems that also require unit conversions, it's a bit unclear, even to me, when...
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