Friction does not care about area

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Friction is primarily influenced by the normal force rather than the contact area, which explains why pulling a table with all four legs on the ground is harder than with only two legs. When all four legs are on the ground, the entire weight of the table contributes to the normal force, increasing friction. Lifting two legs reduces the normal force, thereby decreasing friction and making it easier to pull the table. This principle aligns with the understanding that friction equations do not include a variable for contact area. Overall, the force required to move an object is directly related to the normal force acting on it.
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I heard the Firction does not care about area or at least the friction equations do not have a varible for area, if that is true then why is it hard to pull something like a table when 4 legs are on the ground then when two legs are on the ground?


- BeachMountain
 
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Friction depends on normal force. If the four legs of the table are on the ground, the whole weight of the table contributes to the normal force. If you lift two legs, you are supporting part of the weight, so the normal force is less.
 
SGT is exactly on the spot with the answer.
 
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