physical science, chapter 3, measurement
The unit accomplishes 3 things:
signals that the preceding number is a measurement, kind of dimension, size of the dimension unit (15 feet)
in 1799 who established a decimal metric system
France
the common abbreviation for the metric system
SI
weight
the force of the earth's gravity acting on the matter of the object- N (newtons) is the metric unit of force
mass
the measurement of the amount of matter in an object (metric unit for mass is kg)
significant digits
a digit in a measurement used to communicate the precision of the measurement
standard
a known quantity of a dimension that everyone agrees to use for comparison when measuring
measured data usually has 2 parts:
a number and a unit ( ex: 12 feet, 82 degrees F, 35 minutes)
scientific notation
a way to express very large or small number or more conveniently
accuracy
an assessment of the measurement error
quantitative data
are numerical measurement
qualitative data
are words descriptions
repeatability
data are close together in all trials
_________ of something is the amount of matter (mass) it contains compared to its ___________
density, volume ( density= mass/volume, mass= density X volume, Volume= mass X density)
sources of measurement of error
environmental conditions, operator error, defective instructions, indefinite nature of matter
data
information collected from scientific observations
precision
is an assessment of the exactness if a measurement
dimension
is any measurable aspect of something ( length, time, temperature, volume, speed)
error
is the difference between the measured value and acceptable value
unit
is the name and size of a portion of a dimension that has a volume of 1
observers are far ______ _______ to misinterpret quantitative data
less likely
what is the metric unit for volume?
liter
matter has 2 dimensions what are they?
mass and volume
metric prefixes
mega- million kilo- thousand deci- tenth centi- hundredth milli-thousandth micro- millionth
what are equal volumetric units?
millimeter and the cubic centimeter
volume
the space enclosed or occupied by an object
volume of a solid object and has a simple geometric shape via be found by the formula :
volume= length X width X height (V=lwh)
the volume of an irregularly shaped object can be found by using the what?
water displacement method
measure
when you compare some aspect of the thing that you are measuring to an appropriate measuring standard