There are many occasions where we do not need an exact answer. Sometimes an order of magnitude calculation will do. This can be especially useful if you have made a complicated calculation using a calculator and you are worried that you might have made a power of ten error, for example.
I can only justify giving my answer to 1 sf because I have rounded the data to 1 sf in my approximation. If I do the same calculation on my calculator I obtain 67 kg. My data are given to 3 sf (for T) and 2 sf (for k). When writing down the result from the calculator, I choose the smaller number (2) and quote my answer to this number of significant figures.
Your organisation does not have access to this article.
Sign up today to give your students the edge they need to achieve their best grades with subject expertise
Subscribe
