What is meant by absolute uncertainty in a set of measurements?

Absolute uncertainty is the range of values within which the true value of a measurement lies.

In any measurement, there is always some degree of uncertainty due to limitations of the measuring instrument and the skill of the experimenter. Absolute uncertainty is the range of values within which the true value of a measurement lies, with a certain level of confidence. It is usually expressed in the same units as the measurement itself.

Absolute uncertainty can be calculated by taking the difference between the maximum and minimum values of a set of measurements, divided by two. For example, if a length is measured to be 10.5 cm ± 0.2 cm, the absolute uncertainty is 0.1 cm. This means that the true value of the length lies between 10.4 cm and 10.6 cm with a 95% level of confidence.

Absolute uncertainty is important in physics because it affects the accuracy and precision of experimental results. It is also used to determine the number of significant figures in a measurement, as the uncertainty determines the last digit that can be reliably reported. By understanding and reducing absolute uncertainty, physicists can improve the reliability and validity of their measurements and experimental results.