Today, we will move away from Design and consider ‘Data Processing and Presentation’ (DCP) aspect 1.
DCP is all about collecting raw data, displaying it and processing it.
DCP aspect 1 deals with correctly and accurately presenting raw data.
Data should be put into a table with a title.
Any raw data collected can be split into qualitative (an observation – eg, I saw some bubbles) and quantitative (eg, 30.5 oC). Tables of data should contain both quantitative and qualitative observations to achieve a ‘c’.
The quantitative data should be put in columns with headings, units and the associated uncertainty for the piece of apparatus.
A good rule of thumb to apply for the uncertainty of the apparatus is to use + / – half the smallest division for ‘analougue’ pieces of apparatus and the smallest division for ‘digital’ pieces of apparatus.
For example, a measuring cylinder (an analouge insterument) may record to + / – 0.1 cm3. Therefore, the uncertainty is half of this value, in other words + / – 0.05 cm3.
A digital balance may record to 0.001g, so the uncertainty is 0.001g.
The value that is being recorded should be of a consistent number of significant figures as the uncertainty.
For example, coming back to the measuring cylinder, volumes such as 3.15 cm3 and 3.10 cm3 are acceptable but not 3 cm3 or 3.1 cm3.
Tomorrow, DCP aspect 2.