It's a Sticking Point

Learn about Amontons’ two laws and find out why weight is not thrown forwards when stopping. We will discuss Jeremy Clarkson’s erroneous views on stopping distances and use TI STEM technology to get t

Author: Ian Galloway

Topic:  Physics  STEM

Tags  Acceleration ,  Data collection ,  Dynamic Systems ,  Newton's law ,  Physics ,  Test of hypothesis ,  TI-Innovator Rover

So, you thought you knew all about frictional forces? Never heard of Amontons’ Laws?  Every high school physics teacher teaches the first law but tends to forget the second.  All of us use the laws every day, almost every waking minute of our lives.  Hardly anybody understands them!  They are the two laws of friction, the first about applied load and the second, now largely forgotten, about the area of contact.  This workshop will guide you through a logical approach to understanding both laws and lead you to an appreciation of why Jeremy Clarkson is so wrong about the stopping distances of cars.  Is weight really thrown forwards when a car stops?  Of course not, but then what exactly is going on when a car stops or starts?  Using the TI Rover and the Vernier force probe you will learn why some car manufacturers still use rear wheel drives…it’s all about friction!

 

The pages in the powerpoint are annotated.  This presentation includes a student activity which is prompted by a cognitive challenge.  

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