Sig Figs and Constants on Exams
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Sig Figs and Constants on Exams
On Dr. Lavelle's site, there's a link to a document with constants (like the speed of light and Planck's constant) that I'm assuming we can use on exams. However, I noticed that some of these constants are fairly long. Are we allowed to round these constants to make them shorter when doing our calculations or is it recommended that we use the full length of the constants listed on the sheet?
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Re: Sig Figs and Constants on Exams
In most of the problems Dr. Lavelle has done in lectures and modules, the constants were rounded to the thousandth place. I would assume we could do the same, but I am not completely sure.
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Re: Sig Figs and Constants on Exams
I don't think the constant matter as much as just making sure you do not round your calculator when doing a problem, and just make sure to keep everything in the calculator until the final calculation where you can round the answer to the proper sig fig.
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Re: Sig Figs and Constants on Exams
You should probably use the full length of the constants listed, but use the correct sigfigs depending on the rest of the problem, just to make sure that your answer is closer to what Dr. Lavelle has as the answer.
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Re: Sig Figs and Constants on Exams
Hi, I think it should be fine to round the constants (just not too much) as long as you keep the proper sig figs for the answer. I don't think it'll make that much of a difference :)
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Re: Sig Figs and Constants on Exams
I think it’s best to use the full length of the constants when you do your calculations and throughout your intermediate work so when you apply sig figs to your final answer it’s as precise as it can be.
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Re: Sig Figs and Constants on Exams
I would recommend using the full length of the constants when applying them in calculations because it gives a sort of "buffer" of accuracy in your final answer. Sure, it may only be one or two numbers off, but I think it is always best to be as accurate as possible with your answers. Using the full length of the constants is only a few more numbers at best and it always helps, so it does not hurt to consider using the entire length of them. In regards to significant figures, this should be based off the measurements mentioned in the problem and not off the constants. Hope this helps you!
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Re: Sig Figs and Constants on Exams
Personally, I think it might be better to use the full length of the constant and only do sig figs at the end. I'm not sure what Dr. Lavelle prefers but I know collegeboard marked questions with premature rounding as wrong. I usually keep the calculations in my calculator and do sigfigs for only my final answer to retain as much precision as possible.
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Re: Sig Figs and Constants on Exams
In our practice problems during discussion sections, the correct answers are always rounded to the appropriate sig figs.
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Re: Sig Figs and Constants on Exams
Hi, I have noticed that in lectures and practice problems the constants are generally rounded but he has said to keep all values and not round until the end number to ensure you get the correct value and number of sig figs so I would not round at first just to be safe.
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