Base units and uncertainties

What is the definition of systematic error?

A systematic error will affect all measurements by the same amount

What is the effect of a systematic error on the gradient of the graph?

It will not affect the gradient of a graph but it will displace it

What are some types of systematic error?

Zero error, parallax

What are some reasons for systematic error?

The way in which measurements are taken, faulty measuring devices

What is the definition of a random error?

A random error is unpredictable

Will a random error affect the gradient of the graph?

Typically yes

How can you reduce the effect of random errors?

Take multiple measurements

What are some reasons for random errors?

Factors that are not controlled in the experiment, difficulty in deciding on the reading given by a measuring device

What is a homogenous equation?

The units on the left are the same as the units on the right

What is the definition of precision?

How close the results are to each other

What is the definition of accuracy?

How close you are to the value you are trying to obtain

What is the absolute uncertainty of a data set?

Half the range

What is the absolute uncertainty of a device?

The smallest scale reading of that instrument

When adding or subtracting uncertainties…

Add the absolute uncertainties

When multiplying or dividing uncertainties…

Add the percentage uncertainties

What happens to the uncertainty when a quantity is raised to the power n?

The percentage uncertainty is increased n times

What does an error bar on a graph tell you?

The absolute uncertainty of a measurement

How do you draw a line of worst fit?

Start at the bottom of the bottom error bar and end at the top of the top error bar