Measurement & Uncertainty

Error that is due to chance and is not standardized. Decreases precision.

Error that shifts all measurements in a standardized way. Decreases accuracy. Can result in bias

A description of how close a measurement is to the true value of the quantity measured.

a measure of how close a series of measurements are to one another

the ratio of the uncertainty of a measurement to the measured value, expressed as a percent- age

Uncertainty of a quantity divided by the value of the quantity. Decimal version of percent uncertainty.

expresses the margin of uncertainty associated with a measurement. For an analogue scale, it is half of the smallest measurement increment. For a digital scale, it is equivalent to the most precise decimal place of the instrument.

A scale with demarcations of the same interval. You can read a measurement based on where it falls on the scale. Read ONE DIGIT past the smallest increment on the scale.

An electronic scale with a sensor that measures a specified amount and displays the result electronically.

All the digits that can be known precisely in a measurement, plus a last estimated digit

the curve at a liquid's surface by which one measures the volume of the liquid

A measurement is reproducible if the investigation is repeated by another person, or by using different equipment or techniques, and the same results are obtained.

A measurement is repeatable if the original experimenter repeats the investigation using same method and equipment and obtains the same results.