Why is the Normal Force Neglected in Certain Scenarios?

Thread starter nomorenomore
Start date Mar 6, 2014
Tags

Force Normal Normal force

AI Thread Summary

The normal force is often neglected in scenarios where an object, such as a wheel, is transitioning off the ground, like when moving up a step. In these cases, if the applied force exceeds the gravitational force, the wheel can lose contact with the surface, resulting in no normal force acting on it. This is because the normal force only exists when an object is in contact with a surface. Understanding when the normal force is present is crucial for analyzing forces in mechanics. Thus, in certain dynamic situations, the normal force may not be applicable.

Mar 6, 2014

nomorenomore

attachment.php?attachmentid=67312&stc=1&d=1394118481.jpg

So why does normal force of the wheel not counted or drawn in the diagram??
Isn't it that whenever there's mg, there's also Fnormal?

Thanks!

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Mar 6, 2014

jackarms

It looks like it's because the problem involves the wheel going up off the ground to the next step, so if the force is large enough, then the wheel will be up off the ground and so there won't be a normal force.

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