2: foundations of physics

name the 7 SI base units

 

Quantity	Unit symbol
Length	m
Mass	kg
Time	s
Electric current	A
Temperature	K
Amount of substance	mol

define systematic error

results are incorrect by the same amount on each reading

define random error

cause readings to be spread about the true value

describe one way to reduce systemic error

calibrate equipment

describe one way to reduce random error

repeat readings + avg

define precision

how close the value is to the true value

define calibrated

accurate scale has been established to a known standard

define resolution

resolution: smallest measurement that can be made by an instrument

describe a reproductive experiment

if laboratory, experimenter and apparatus are different but have the same conclusion, experiment is reproductive

describe a repeatable experiment

if laboratory, experimenter and apparatus are the same but have the same conclusion, experiment is repeatable

how to know if a value for a constant is accurate

value for a constant is accurate if % uncertainty > % difference

how does a vector triangle show that the forces are in equilbrium

all arrows point tip to tail, closed triangle is formed