Mini-Quiz: Causes of Friction

1. What causes adhesion of two materials?

   The tiny bumps make sliding motion more difficultGood try, but not right. Select another answer. Water will stick to anything, increasing frictionSorry, not correct. Try another button. Electromagnetic attraction when molecules are in close proximityThat is correct. You must be a Science Champion.

2. What effect does surface roughness have on friction?

   It is the main reason for frictionOops! Wrong answer. Re-read the question and try again. It only has a small effect unless the roughness is extremeCorrect. You know your friction. It depends if the materials are solids or liquidsSorry, not correct. Try another button.

3. What is the major cause of friction when sliding a heavy box through mud?

   Deformation or plowing frictionThat is correct. You must be a Science Champion. Molecular attraction of the mud to the box materialGood try, but not right. Select another answer. Kinetic or moving frictionOops! Wrong answer. Re-read the question and try again.

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