This Lab uses your phone (or an ipad) and an App called Phyphox. An alternative option is given for students who do not have the smartphone.

Each lab counts for 20 points and it is about 1.42% of the total grade, each little point counts, do not miss it!

Introduction

Frictional forces between two solids arise from the interlocking between the two contact surfaces. The resistance to the motion (friction) typically is proportional to the force that pressures the two surfaces together and to the materials themself. This pressure force is perpendicular to the surfaces and it is called normal force N. Imagine placing a block on a flat surface, like the floor for example, the normal force is the floor support force of the block against the pull down of the force of gravity. The normal force in this case is balancing the weight mg of the block and it is equal to the weight of the block.

On an inclined plane, instead the supporting force N is less than the weight mg of the block and the block could slide down pulled by the force of gravity, precisely pulled by the component of the force of gravity along the inclined plane.

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