Lesson 2 Flashcards
(20 cards)
What are the primary causes of measurement errors?
Errors arise due to several causes, such as human errors or errors in using an instrument for an application for which it has not been designed.
Define accuracy in measurement.
Accuracy refers to how closely the measured value agrees with the true value of the parameter being measured.
How is accuracy typically defined for electrical instruments?
Accuracy is usually defined as a percentage of full-scale deflection.
What does precision mean in the context of measurement?
Precision means how exactly or sharply an instrument can be read and how closely identically performed measurements agree with each other.
Fill in the blank: The resolution of an instrument is the smallest change in the measured value to which the instrument will _______.
[respond]
What is the range of an instrument?
The range refers to the minimum and maximum values of the input variable for which it has been designed.
What is bandwidth in relation to measurement instruments?
Bandwidth is the difference between the minimum and maximum frequencies for which an instrument has been designed.
Define sensitivity in measurement.
Sensitivity is the degree of response of a measuring device to the change in input quantity.
What does uncertainty represent in measurement?
Uncertainty is an estimate of the possible error in a measurement and the range of values that contains the true value.
What is a confidence interval?
The confidence interval is the range of values that corresponds to the stated uncertainty.
Define confidence level.
Confidence level is the probability associated with a confidence interval.
What is repeatability in measurements?
Repeatability is defined as the degree of agreement among independent measurements of a quantity under the same condition.
How is reproducibility defined in measurement?
Reproducibility is the closeness of agreement between the results of measurements of the same measurand at different locations by different personnel using the same measurement method in similar environments.
List the four types of measurement errors.
- Human errors
- Systematic errors
- Random errors
- Applicational errors
What are human errors in measurement?
Human errors are generally the fault of the person using the instruments and are caused by incorrect readings or recording of experimental data.
What causes systematic errors?
Systematic errors result from problems with instruments, environmental effects, or observational errors.
What are random errors?
Random errors are unpredictable and occur even when all known systematic errors have been accounted for, often caused by noise and environmental factors.
What leads to applicational errors?
Applicational errors are caused by using an instrument for measurements for which it has not been designed.
How can measurement uncertainties be controlled?
Measurement uncertainties can be controlled by determining the effects of systematic and random errors in all processes that lead to the assignment of a value to a measurement result.
What is the offset in measurement terms?
Offset is the difference between a target (normal) value and the actual value.
