1. AS Physics – Physics: the science of measurement Mr Ewart v1 07/05 1 1 Making measurements precisely Measuring instruments From smaller than the nucleus of the atom, to the giant scale of galaxies, from events that take place in less than a billionth of a second, to the age of the universe: measurement is central to the study of physics. Measurement allows us to study the properties of different objects and to compare properties between objects. In order to discuss and to compare our measurements universally, we must apply a standard system of units to our measurements. Micrometer screw gauge Resolution Vernier scales Uncertainity and precision Percentage uncertainity

2. AS Physics – Physics: the science of measurement Mr Ewart v1 07/05 2 3 The International System of Units Base Units http://www.npl.co.uk/reference/National Physical Laboratory Measurements and units

3. AS Physics – Physics: the science of measurement Mr Ewart v1 07/05 3 Derived quantities 4 Derived quantities and units Derived units Homogeneity Examples of derived units