Transition Work Flashcards
When is a measurement valid?
When it measures what it’s supposed to be measuring
When is a result accurate
When it’s close to the true value
What are precise results
When repeat measurements consistently agree with each other
What is repeatability
How precise measurements are when repeated by the same person, with the same equipment and under the same conditions
What is reproducibility?
How precise measurements are when taken by a 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 is a random error?
An error caused by results varying around the true value in an unpredictable way
What is a systematic error?
A consist difference between the measured values and true values
What does zero error mean?
A measuring instrument takes a false reading when the true value is supposed to be zero
Which variable is changed or selected by the investigator?
Independent variable
What is the dependent variable?
A variable 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 contains protons and neutrons surrounded by electrons on shells
