What causes systematic error in measurements?

Systematic error in measurements arises from consistent and repeatable inaccuracies associated with a particular measurement process or equipment. When focusing on measuring devices, it is crucial to understand that inherent biases in the design, calibration, or functioning of these tools can lead to systematic errors. For example, if a scale is incorrectly calibrated, it will consistently produce measurements that deviate from the true value by the same amount each time it is used, regardless of the sample being weighed.

This type of error is distinct from random errors, which result from unpredictable fluctuations and can vary widely between measurements, or from environmental factors that may intermittently affect readings. Although environmental conditions can lead to errors, they are typically categorized as random unless they cause a permanent change in the measurement equipment itself or its settings. Similarly, incorrect calculations can lead to inaccuracies, but they do not reflect the inherent bias introduced purely by the measuring devices used. Thus, systematic error fundamentally stems from the characteristics and performance of the measuring instruments employed in the process.