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Friction experiment for 4th grader

2005

All,

I'm writing this for my 4th grader.

I am interested in minimizing two different friction drivers. The first is minimizing the force required to initiate movement from a standing stop to rolling. And minimizing "rolling friction" . The characteristics of the problem are:

light load 5 ounces or less. curved surfaces, imagine an axle and wheel problem key driver is to minimize the friction betwee a steel "axle" and a plastic "wheel".

Wear characteristics are not a big issue, but constancy of performance over 20-30 trials is important.

The drive is minimum friction.

Thanks

Andy

D. Andrew Pappal
hobbyist - Ocean City, New Jersey

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The smoother the materials, the lower friction you will see. If oil is allowed, it will make a tremendous difference compared to surfaces that are well cleaned and oil free. Set up a level surface like a table top, checking it with a level, and use a light, calibrated spring (like a light 'fish scale' available at a tackle store) to see how much force is required to get a weight sitting on four such wheels rolling and keep it rolling.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005