** Next:** Dimensional analysis
** Up:** Introduction
** Previous:** Other units

In this course, you are expected to perform calculations to a relative accuracy
of 1%: *i.e.*, to *three significant figures*. Since rounding errors tend
to accumulate during lengthy calculations, the easiest way in which to
achieve this accuracy is to perform all intermediate calculations to
*four significant figures*, and then to round the final result down to three significant figures.
If one of the quantities in your calculation turns out to the the small difference between
two much larger numbers, then you may need to keep *more* than four significant figures.
Incidentally, you are strongly urged to use *scientific notation* in *all* of your
calculations: the use of non-scientific notation is generally a major source of error
in this course.
If your calculators are capable of operating in a mode in which *all* numbers
(not just very small or very large numbers) are
displayed in scientific form then you are
advised to
perform your calculations in this mode.

Richard Fitzpatrick
2006-02-02