Bridge Work Flashcards
When is a measurement valid?
when it measures what it is supposed to be measuring
When is a result accurate
when it is close to the true value
What are precise results
when repeat measurements are consistent/agree closely with
each other
What is repeatability?
how precise repeated measurements are when they are taken
by the same person, using the same equipment, under the
same conditions
What is reproducibility?
how precise repeated measurements are when they are taken
by different people, using different equipment
What is the uncertainty of a measurement?
the interval within which the true value is expected to lie
Define measurement error
the difference between a measured value and the true value
What type of error is caused by results varying
around the true value in an unpredictable way?
Random error
What is a systematic error?
a consistent difference between the measured values and true
values
What does zero error mean?
a measuring instrument gives a false reading when the true
value should be zero
Which variable is changed or selected by the
investigator?
independent variable
What is a dependent variable?
a variable that is measured every time the independent
variable is changed
Define a fair test
a test in which only the independent variable is allowed to
affect the dependent variable
What are control variables?
variables that should be kept constant to avoid them affecting
the dependent variable
What does an atom consist of?
a nucleus containing protons and neutrons, surrounded by
electrons
