Module 1 (Appendix) Flashcards
What is a true value?
The value that would be obtained in an ideal measurement.
What is a measurement error?
The difference between the measured value and the true value for the quantity being measured.
What are random errors and how can they be caused?
Measurement errors in which measurements vary unpredictably. They cannot be corrected.
They may be caused by: factors that are not controlled in the experiment, difficulty in deciding on the reading given by the measuring device.
What are systematic errors?
Measurements differ from the true value by a consistent amount each time the measurement is made.
What is accuracy?
How close a measured result is to the true value.
What is precision?
How close repeated measurements are to each other.
How can you approximate absolute uncertainty?
Half the range.
How can you calculate percentage uncertainty?
(absolute uncertainty)/(mean value) x100
How can you approximate absolute uncertainty when the range is 0?
The absolute uncertainty will be the resolution of the measuring equipment.
How do you calculate uncertainty when adding or subtracting?
Add the absolute uncertainties for each value.
How do you calculate uncertainty when multiplying or dividing?
Add the percentage uncertainties for each value.
How do you calculate the uncertainty for data on a graph?
The absolute uncertainty for gradient is positive difference between the gradient of the line of best fit and the line of worst fit.
