Measurement and Vectors
Summary
Physics is an experimental science in which measurements made must be expressed in units. In the international system of units (SI system), there are seven fundamental units in terms of which all physical quantities are expressed, either directly, or as a combination.
A measurements is characterized by its accuracy and precision. Accuracy is how close a measurement is to the correct value for that measurement. The precision of a measurement system refers to how close the agreement is between repeated measurements (which are repeated under the same conditions).