Getting to know your smartphone magnetometer
Skills and concepts that students must have mastered
How the activity is situated in the course
Activity LengthMax of 1-2 hours.
Content/concepts goals for this activity
- collect magnetic data using their smartphones, with an understanding of the sensors operation and limitations;
- understand the nature of the Earth's magnetic field and how it varies with geographic location.
- understand the nature of magnetic anomalies as deviations from expected reference field.
Higher order thinking skills goals for this activity
- 3D visualisation
- evaluation and comparison of data from different sources
Other skills goals for this activity
Description and Teaching Materials
Student Handout (Acrobat (PDF) 599kB May29 20)
Instructor Handout (Acrobat (PDF) 219kB May29 20)
Intro to Geomagnetic Field - Slides (PowerPoint 2007 (.pptx) 4.4MB May29 20)
Technology NeedsStudents will need access to a smartphone with the Physics ToolBox Sensor Suite (a free app available on iOS and Android) installed. A computer and spreadsheet software is ideally needed to analyse the collected data, but this would be possible on a smartphone.
Teaching Notes and Tips
I suspect the most difficulty will come when students assigning the (x,y,z measurements to specific physical sensor axes, and particularly the sign of the z axis).
- locate sensor and assign sensor axes correctly
- take x,y,z measurement and correctly derive the field inclination.
- understand possible sources of deviation from reference field values.
References and Resources
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