Uncertainty measures the lack of certainty or sureness of an outcome.
Uncertainty of a measured value can also be presented as a percent or as a simple ratio.
Formula to calculate percent uncertainty.
When calculating percent uncertainty, absolute uncertainty is used.
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Example:
Suppose you measured the quantity of a solution using a measuring cylinder and found it to be 25.2 cubic centimeters, if the uncertainty value is ± 0.05, calculate the percent uncertainty.
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Therefore, the percent uncertainty is 0.2%.