Conversions
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Conversions
I keep having calculation mistakes when solving problems so I just want to double check with how I am inputting my numbers into my calculator. Typically I don't round my sig figs until I have my final value to avoid computational error. When it comes to prefixes, should you input the number into your calculator as the exponent value, keeping mind of parentheses for negative values, or should you convert to long decimals/numbers?
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Re: Conversions
Hi Darcy,
When I do calculations with non-base units, I always convert them by base 10 exponentiation in my calculator. I personally feel that typing in the decimal value introducess more potential for error. For instance, something like F = ma where m = 3kg and a = 2nm/s2, I would type in 3 * (2 * 10^-9). I have a graphing calculator, so this is easier to type into the interface. Sometimes calculators have "E" as the symbol for exponent with base 10. I could also enter the aforementioned expression into my calculator as 3 * 2E-9, which would yield the same result. I hope this helps!
When I do calculations with non-base units, I always convert them by base 10 exponentiation in my calculator. I personally feel that typing in the decimal value introducess more potential for error. For instance, something like F = ma where m = 3kg and a = 2nm/s2, I would type in 3 * (2 * 10^-9). I have a graphing calculator, so this is easier to type into the interface. Sometimes calculators have "E" as the symbol for exponent with base 10. I could also enter the aforementioned expression into my calculator as 3 * 2E-9, which would yield the same result. I hope this helps!
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Re: Conversions
I think it all depends on the type of calculator you have. I also have a graphing calculator like Darcy and I do the same. But if you're using scientific, maybe doing the calculations in multiple steps instead of putting it all in might help?
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Re: Conversions
Hi! I do the same thing with using the whole values/strings within my calculator. If you have a scientific/graphing calculator, you can always scroll up and select previous values to compute with, and take multiple steps if there are too many calculations needed. Oftentimes, I run into PEMDAS problems if I try to cram everything into one equation and am not careful about parentheses. And if you need to abbreviate a value with many zeros, you can also use the EE button, which creates a small (E) standing for 10^, and then you enter in the value of your exponent. This helps reduce human/computational error! Finally, at the end, I usually round to the sig figs needed from the problem description, but everyone has a different style of calculating and it's up to you how you do it!
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Re: Conversions
When converting to different units I keep it with exponents if possible so it's more accurate, if not keep as many decimal places as possible until your final answer.
Re: Conversions
While using a calculator, I usually tend to use parentheses around each value to avoid errors. Moreover, I prefer values with prefixes over the long decimal numbers because it makes the calculation easier. Try doing the problems in multiple steps rather than just one step.
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Re: Conversions
I much prefer inputting the scientific (exponent) form over the decimal form. Also I use the E function rather than typing 10^x since this tightens up the calculations. Also when doing addition/subtraction with multiplication/division in one calculation, use a lot of parentheses so you don't run into any PEMDAS issues. Lastly, when solving for a big equation like the Rydberg formula or the Heisenberg uncertainty principle, take it one step at a time instead of solving the entire thing in one go. In my experience, doing a big calculation often results in a PEMDAS error somewhere.
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