Why does friction remain constant with larger surface area?

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Frictional force is independent of the contact area, as described by the equation F=μN, where area does not factor in. The confusion arises from the belief that larger surface areas lead to more interlocking of surface irregularities, which would suggest increased friction. However, with a constant mass, a larger surface area distributes the weight over more area, reducing the pressure on each unit area. This results in a constant frictional force regardless of surface area. Understanding this principle clarifies why friction remains constant despite changes in contact area.
takando12
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My books and my teachers tell me that the frictional force is independent of the area of contact. I am also aware of the equation F=μN and that area has no part in it. But it's just so confusing and counter-intuitive.
Friction is because of the the interlocking of the irregularities of two surfaces (At least that's what i think it is). So doesn't more area mean , more interlocking and hence more friction?
Please do help me understand this.
 
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For an object whose mass is constant and shape can be deformed, the larger the one of the object's surfaces is, the less the gravity that unit area carries gets, so the frictional force remains also remains constant.
 

Thread 'Mousetrap Car Energy efficiency'

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