Edexcel A Level Physics:复习笔记1.5 Scientific Communication

Scientific Communication

  • Scientific communication of the results of an experiment are extremely important
  • The ideas must be communicated in an appropriate way using appropriate terminology
    • This involves using terms such as accuracy, validity and stating the sources of random and systematic errors
  • Scientists have to design an experiment to answer a question or investigate something
  • These will involve dependent and independent variables
    • An independent variable is what is changed
    • A dependent variable is what is measured
    • The control variables are what do not change
  • For example, in an investigation of the variation of potential difference and current across a light bulb
    • The independent variable is the potential difference
    • The dependent variable is the current
    • The control variable would be the temperature of the apparatus
  • Data must always be presented in a scientific way
  • This may include:
    • Tables
    • Graphs
    • Diagrams


Presenting Data in Tables

  • When taking readings, a sensible range should be taken, and the values should all be stated to an appropriate number of significant figures or decimal places
    • This is usually the same number as the resolution of the measuring instrument


  • The columns in any table should have both a quantity and a unit in their heading
    • When labelling columns, the names of the quantities should be separated from their unit by a forward slash ( / )


  • For data displayed in a table:
    • The first column should contain the independent variable
    • The second column should contain the dependent variable
    • If repeat readings of the dependent variable are required, these should be included with a column for the mean value at the end
    • Any columns required for processing data e.g. calculations should come after this


    Conventions for presenting data in a table. The length is the independent variable and the frequency is the dependent variable


  • In summary, when presenting tables the following must be included:
    • Clear headings, or symbols, for columns
    • Relevant units for measurements
    • Readings listed to the same number of significant figures



An example of a correctly labelled table with corresponding graph


Presenting Data on a Graph

  • All readings, including suspected anomalous results, should be plotted on a graph so that they can be easily identified
  • When taking repeat readings, it is the mean value that is plotted
  • The way data is presented on a graph depends on what type of data it is

Discrete data

  • Only certain values can be taken, normally a whole number e.g. number of students
    • This should be displayed on a scatter graph or bar chart


Continuous data

  • Can take any value on a scale e.g. voltage in a circuit
    • This should be displayed on a line or scatter graph


Categorical data

  • Values that can be sorted into categories e.g. types of material
    • This should be displayed on a pie or bar chart


Ordered data

  • Data that can be put in ordered categories e.g. low, medium, high
    • This should be displayed on a bar chart


  • In summary, when presenting graphs the following must be included:
    • An explanatory title
    • Clearly labeled axes
    • Relevant units for measurements
    • Well plotted points
    • A smooth line or curve of best fit




An example of a correctly labelled and plotted graph


Presenting Diagrams

  • When presenting diagrams, such as apparatus set-up, all the relevant parts must be clearly labelled



An appropriately labeled diagram of the set-up of an investigation into simple harmonic motion