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measurement

is a comparison of a dimension of an object or substance to an appropriate standard, usually an instrument with a calibrated scale.

standard

is a known quantity that everyone agrees will be used for comparison when measuring

instrument

any artificial device made for the purpose of refining, extending or substituting for the humans senses when measuring

dimension

a property that can be measured

calibrated scale

the spacing of the marks on the instrument

unit

the segment of a dimension assigned a value of 1 for measuring

metric system

measures meter (m) and the kilogram (kg)

measured data

has two parts:

1) a number that gives the size of the measurement

2) dimensional unit

1) a number that gives the size of the measurement

2) dimensional unit

observational bias

is a flawed perspective on data that results from a person's desire to see a certain outcome

qualitative data

described data

quantitative data

numerical data

accuracy

is an assessment of the measurement error

calibrated

..., -marked with measurements

mass

amount of matter in a given volume

objective observation

a more precised(exact) observation, more accurate-(it is not possible to be exact, but close)

subjective observation

not as precised as the projective observation

SI

Le Système International d'Unités, or the International System of Units, which is the measurement system that is accepted worldwide...METRIC SYSTEM

conversion factor

any factor (mulltiplier) used to convert from one unit of measure to another.

error

difference between a measuremnt and the actual value

accuracy

is an assessment of the measurement

precision

exactness, accuracy of a measurement

significant digit (SD)

a digit in the measurement used to communicate the precision of the measurement.

scientific notation

a convenient way to express very large or small numbers in the form of M x 10, an expression of numbers in the form m × 10n where m is equal to or greater than 1 and less than 10, and n is an integer, a way of writing very large or very small numbers using a number between 1 and 10 multiplied by a power of ten

weight (w)

force of gravity pull on the matter in an object

spring scale

an instrument that measures weight by balancing the pull of the earth's gravity on the object being weighed

electronic balance

an electronic instrument that measures the weight of an object and then displays is equivalent mass

balance

an instrument that compares a known mass to an unknown mass. when balanced the weight of the object with unknown mass equals the weight of the known mass.

volume

the space enclosed or occupied by an object

meniscus

The curved surface of a liquid

density(ρ)

the amount of mass of the substance contained in a specific volume

electronic scale

object to be weighed is placed on a metal plate on top of the instrument. the scale converts the pull of gravity on the object into an electronic signal - weight is displayed on a digital screen.

Law of mass conservation

mass is neither created or destroyed-physical or chemical change of matter is the same before after