FrictionFrictionFormulate at least 4 important facts Formulate at least 4 important facts

about frictionabout friction

Objective 2 vocabulary:friction resistance magnitudestatic sliding friction static frictionrolling friction

Objective 2 Definitions:Friction -a force that resists motion when 2 objects are touching / the resistance force between 2 objects that are ‘touching’ Resistance – opposition by a forceMagnitude – the size of something, the strength of a forceSliding friction - the friction force that resists the motion of an object moving or sliding across a surfaceStatic friction - the friction force that resists the motion between 2 surfaces that are not moving. (static means unchanging)Rolling friction - the friction force that resists the motion of an object rolling across a surface

Important points to know about Frictionoccurs when two objects come into close contact always acts to slow down the motion of objectsThe direction of the friction force is always opposite the motion of the objectcaused by differences in the microscopic surfaces; the molecules in the two materials attract each other (this is called adhesion). When you slide one object past another you need to break these bondschanges energy of motion into heat energy

Friction ForceFriction Force Rolling, sliding & static friction - what is the Rolling, sliding & static friction - what is the

difference?difference? Draw & share an example of each that includes Draw & share an example of each that includes

a force diagram.a force diagram.

Lab report discussion: Lab report discussion: Hypothesis writingHypothesis writing

What is a hypothesis? Why is it important to form a

hypothesis before you start an experiment?

What are the parts of a hypothesis? What makes a good hypothesis?

Make hypothesis based on the Investigation question: Which surface will produce more rolling friction with a marble: plastic, carpet or tape?