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STLRamsFan
May 23rd, 2012, 10:14 PM
An easy physics question but I'm struggling to put this into words... Brain fart I guess you can say haha.

Explain how "least count", "precision", and "uncertainty" are related?
Donut
May 23rd, 2012, 10:31 PM
im not sure about that first one, but have you ever heard of heisenberg's uncertainty principle? the majority of it is needlessly complicated for this example, but the idea behind it is that by observing something, or measuring it, you change it. let me explain with an example:

you run a benchmark program to test your computer's performance. this program can take a sample of how much the computer is struggling to render the scene every x units of time. the more frequently you take samples, the more accurate, or precise the readings are.

BUT, because some of that power goes to running the benchmarking software, youre not getting an absolutely perfect reading. you need to use some of the processing power to observe the processing power.

so, the more samples of processing power you take (re: the more precise you are), the less certain you are of the computer's ACTUAL processing power, since some of it is being used to take those samples.

hope that made sense.
n00b1n8R
May 23rd, 2012, 10:51 PM
http://elchem.kaist.ac.kr/vt/chem-ed/data/graphics/acc-prec.gif

Accuracy is how close a value are to a "true" value. Precision is the repeatability of you attempting to arive at the "true" value.

Least count is the finest precision possible (eg with a normal ruler you can measure accurately to ~0.5mm)

Uncertainty is the range of error attached to any measured value (eg you could measure to that 0.5mm but you'd have an uncertainty of say ±0.25mm)

Surely you could have googled this?
neuro
May 24th, 2012, 12:51 AM
if it's an easy question, WHY DO YOU NEED US TO ANSWER IT FOR YOU?? HMM?? HMMH??
STLRamsFan
May 24th, 2012, 01:16 AM
Only put that to make myself feel better. :iamafag:
But I think I got it with the help from above.
Limited
May 28th, 2012, 06:35 AM
They all have only one E. Probably not the answer they are looking for.
=sw=warlord
May 28th, 2012, 07:22 AM
lower the count the lower the uncertainty, the higher the precision the less count is needed.
STLRamsFan
May 28th, 2012, 10:09 PM
They all have only one E. Probably not the answer they are looking for.

Haha! Cannot tell you how close I was to actually putting that as my answer. Just goes to show you how much I actually care for physics...