unit

measurement is comparison of a physical quantity to be measured with some fixed standard

precision

closeness of the set of values obtained from identical measurements of a quantity of the same instrument

accuracy

closeness of a single measurement to its true value

percent error

taking a percentage from the absolute value of the difference between the experimental number (xe) and the correct number (x) divided by the correct number

standard deviation

measures how closely data are clustered about average value

density

physical property of a substance; all forms of matter, whether solid, liquid, or gas, have density

displacement principle

if an object is submerged in a liquid, it will displace a volume equal to the volume of the object itself