What does "maximum possible error" refer to?

"Maximum possible error" refers to the maximum amount by which a measured value could deviate from the true value within the constraints of the measurement process. It is determined by considering the precision of the measuring instrument, typically represented by the smallest unit of measurement employed.

When approximating maximum possible error, the standard practice is to use half the value of the smallest unit of measurement. This approach allows for the understanding that the true value could be anywhere within the range defined by the smallest measurement, making it a reliable estimate for potential inaccuracy. For instance, if a ruler measures in centimeters, and the smallest unit is 1 cm, the maximum possible error would be ±0.5 cm, acknowledging that the true measurement could be 0.5 cm less or more than the indicated reading.

This concept is vital for understanding the limits of precision in measurement and how these limits affect the interpretation of experimental data. Recognizing maximum possible error helps in evaluating the reliability and accuracy of collected data, ensuring that conclusions drawn from measurements are as sound as possible.