Measurement, Errors and Graph Skills

Vocabulary flashcards covering measurement definitions, resolution, accuracy, precision, uncertainty, and types of experimental errors.

Resolution

The smallest change that a measuring device can detect in the variable being measured.

Continuous variable

A variable that can have numerical values, such as length of a wire.

Accuracy

A property of a measured value indicating that it is close to its true value.

Precision

A quality of measurements describing very little spread about the mean value; it depends solely on the extent of random errors and gives no indication of closeness to the true value.

Target representation of accuracy and precision

A visual model demonstrating that arrows striking close to the center indicate high accuracy, while arrows grouped close together indicate high precision.

Error (in science)

A condition indicating that a measurement made is not exactly equal to the true value, which does not necessarily mean that a mistake was made.

Random error

An error that causes readings to be spread about the true value due to results varying in an unpredictable way from one measurement to the next; it is present in every measurement, cannot be eliminated, but its effect can be reduced by making more measurements and calculating a mean.

Systematic error

An error that causes readings to differ from the true value by a consistent amount each time a measurement is made, arising from the environment, observation methods, or equipment, and cannot be addressed through simple repeats.

Measure of uncertainty

The range of a set of measurements assessed about the mean value.

Scatter (on a scatter graph)

The dispersion of data points about both sides of the best fit line caused by random error, where greater random error results in points being scattered further from the line.