Significant Figures for Constants [ENDORSED]
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Significant Figures for Constants
This may have been asked before, but how many significant figures should we write down and put into our calculators when using some of the constants on the constants and equations sheet?
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Re: Significant Figures for Constants
I would use whatever the constants/equations sheet gives you to maintain accuracy, but if you are in a time crunch, 3 sig figs should be okay.
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Re: Significant Figures for Constants
Typically, you should use however many significant figures are on the equations sheet and round with sig figs at the end of the question, depending on the given values. This is the best way to avoid a rounding error.
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Re: Significant Figures for Constants
I always try to follow the number of sig figs used in the question, but I often will just do 3 sig figs since anything more than that can't really affect the answer to the question.
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Re: Significant Figures for Constants
Personally I believe its best to plug in the same number of sig figs that is given for the constants value so that you can get the most accurate answer and then once you get the answer you can round your answer to the correct amount of sig figs.
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Re: Significant Figures for Constants
I have the values saved in my calculator as they are written on the constants and equations sheet, as I figured that those would be the values that would give us the right answers on the tests seeing as they were given
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Re: Significant Figures for Constants
I think especially when it comes to predetermined constants, it's safest to use the full value of the constant while you're doing calculations, and then you can account for sig figs in your final answer.
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Re: Significant Figures for Constants
To be safe it may be best to use all the figures but more than 4 sig figs probably won't change the answer too much.
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Re: Significant Figures for Constants
I think it is best to use the entire number when it is given and only account for sig figs at the end.
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Re: Significant Figures for Constants
If you are aiming for accuracy, it is best to use the full number from the equation sheet just to be safe. When writing it out, I do not think you need to write out the entire number, but you can plug it into your calculator as is given on the sheet. But using 3-4 significant figures will usually not have a large, if any, impact on your answer.
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Re: Significant Figures for Constants
I always follow whatever is given to us on the constants and equations sheet, but if not, then at least the same sig figs as the problem.
Re: Significant Figures for Constants
I usually follow what's on the constants and equations sheet, and then round for the final answer, but usually 3 to 4 sig figs the way to go.
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Re: Significant Figures for Constants
I would use as many as you can from the constant/equations sheet just to be more precise and then round at the end of all your calculations
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Re: Significant Figures for Constants
Hi, I tend to base how many sig figs I use on how many are given in the stated problem and I try to be consistent with the sig figs of all the constants that I use when solving.
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Re: Significant Figures for Constants
Does anyone know how the achieve homework is graded in relation to sig figs? I've been stuck on a couple of questions and realized I only got the answer wrong due to using the incorrect amount of sig figs.
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Re: Significant Figures for Constants
Always try to use the least amount shown, but I would say 3 or 4 to be safe.
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Re: Significant Figures for Constants
I would try to use the complete number when using the constants but again if you are in a time crunch like a test I always try to use atleast 3-5 sig figs to make sure that my answer is accurate.
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Re: Significant Figures for Constants
3 sig figs is what he usually uses in notes and lectures but obviously the more the better for accuracy. If you are saving them in a calculator, I would save them the way the formula sheet has it. On the Achieve hw, they seem to take 2-3 sig figs usually.
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Re: Significant Figures for Constants
Hi! To be safe, I would use all of the sig figs given on the constants and equations sheet, but if you are pressed for time, I would say 3-4 after the decimal would probably be fine. However, I would still use all of the sig figs given on the sheet just to be careful. Hope this helps!
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Re: Significant Figures for Constants
I just use how many sig figs are on the equation sheet and then use how many ever sig figs are in the problem when writing my answer.
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Re: Significant Figures for Constants
I try to use as many from the equation sheet but if I want to do it quickly I usually use three to four sig figs but it's better to use all of them so you can get an accurate answer.
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Re: Significant Figures for Constants
Three significant figures is usually what I use, but as long as you use the number of sig figs given on the formula sheet, you will get an acceptable answer.
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Re: Significant Figures for Constants
I try to maintain the number of sig figs initially established in the question, but rounding to 3 is usually a safe bet.
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Re: Significant Figures for Constants
On tests where the exact answer could be more important, I use all of the significant figures given on the equation sheet. For more casual assignments like homework, I usually use 3 significant figures after the decimal point.
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Re: Significant Figures for Constants
I would try to maintain the same number of significant figures that is described in the question for your answer. A general rule of thumb is that rounding to about 3 sig figs is best, but Dr. Lavelle has emphasized that sig figs are not heavily emphasized nor critiqued at this level of chemistry.
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Re: Significant Figures for Constants
For calculations, I am pretty sure it was recommended to use all the given numbers and store them in your calculator as you solve the problem. That way your answer is as exact as possible. For achieve homework I would just mirror whatever sig figs where used in the given info of the problem, but from my experience it didn't matter how many I put.
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