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1.1: Interpreting Errors

  • Page ID
    29118
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    Systematic Error

    • Measurements deviate from the correct value by the same amount each time
    • Errors have a pattern

    Example:  Time on a watch is always 5 minutes ahead of the true time

    Random Error

    • Errors have no pattern 

    Example:  Everyone’s watch shows a different time

    Uncertainty in Measurement 

    • Number ± error
    • It is the amount a number may be off from the correct value

    Example:  Age ±365 days

    Ratio Comparison

    • Shows how two numbers compare
    • Reduced fraction shows comparison

    Example:  

    \[\dfrac{65 \text{mph}}{30 \text{mph}} = \dfrac{2.2}{1}  \text { (Means one speed is 2.2 times faster than the other)}\nonumber \]

    Percent Error

    • Percentage measurements are off from standard/correct value
    • Absolute value

    \[\text {Percent Error}  = \dfrac{\text {Experimental/Measured Value} - \text {Accepted/Theoretical Value}}{\text {Accepted/Theoretical  Value}} \times 100 \% \nonumber  \]

    Contributors and Attributions


    1.1: Interpreting Errors is shared under a CC BY license and was authored, remixed, and/or curated by LibreTexts.

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