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Page history last edited by johnlittlephysics 2 years, 10 months ago


  • Introduced in Physics Olympiad from about 2011
  • Introduced in Physics from about 2014
  • Introduced in Advanced Physics in 2017

About Tracker

Useful tips 

  1. Object-background contrast:
    • Ensure consistent large contrast between moving object and its background.
    • Avoid sudden change in contrast or colour from wall to floor. 
  2. Plane of ruler & object's path: 
    • Ensure that camera captures the ruler placed in the same 2D plane as the path of the moving object, so that x and y coordinates are accurate.
    • Any 3D motion may need another camera to capture the 3rd dimension.
  3. Manual tracking:
    • Instead of choosing "Autotracker", we can manually track the ball's position by holding shift button and clicking the mouse at the ball's position.
    • The video frame would automatically move to next frame (can increase Step > 1).
    • Continue shift+click till end of the last frame chosen. This is more tedious but may be more accurate. 

Resource files


Lesson examples


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