The formula for the calculation of friction, F=uN, where u is the friction coeficient, doesn't include anything related with its area of contact.(adsbygoogle = window.adsbygoogle || []).push({});

That is, to what I know, a rectangle for example, weighing 3 kg that is real long and has little height, has a big area of contact with the surface it is on, compared to a block for example, of the same weight . I think that the rectangle is harder to move because of its much bigger area of contact.

I know that because it has a big area of contact then its weight is distributed and so it has less Newtons per cubic m.

However I still think that the rectangle should have a greater friction than the cube..am I right?

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# Homework Help: Friction question

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