Applied Science AQA/Resistivity Portfolio
Syllabus Content[edit | edit source]
Materials scientists need to be able to recommend appropriate materials for electrical components in a huge range of products.
In completing investigations, learners will develop their knowledge and understanding of the following concepts:
• the meaning of resistivity
• how the resistance of an electrical component relates to the resistivity of the material it is made from
• importance of knowing the resistivity of a material
• uses of materials with both high and low values of resistivity, including, for example, new semiconductors used in electronic circuits
• use of standard procedure to measure the resistivity of a piece of wire
• accuracy and reliability of data, recorded with appropriate precision
• methods used in industry
• recording appropriate measurements:
• calculate a value for the wire’s resistivity
• calculate the theoretical percentage error
• calculated value compared with researched value for resistivity of the wire’s material
• reasons for differences between theoretical and calculated values
• evaluation of methodology.
The Brief[edit | edit source]
Advice[edit | edit source]
DON'T just copy and paste anything! You can't get any marks for something someone else wrote.
Use the official glossary to clarify the meanings of the words accurate and precise.
Checklist - before you hand in:[edit | edit source]
Have you:
Pass[edit | edit source]
- Given a definition of resistivity
- Explained the differences in behaviour between materials with a high and a low resistivity, using examples
- Carried out the experiment and found a value for resistivity - with units (probably from a graph gradient)
- Written a full risk assessment
Merit[edit | edit source]
- Chosen examples of materials with high and low resistivities and explained why these materials are used for particular purposes in industry
- Compared the value from your resistivity experiment with an official value - evaluated and explained why yours is different.
Distinction[edit | edit source]
- Written about industrial methods for finding resistivity- and explained how they are both more accurate and more precise than your classroom method - e.g. the conditions in which they are carried out