Why does friction remain constant with larger surface area?

  • Context: High School 
  • Thread starter Thread starter takando12
  • Start date Start date
  • Tags Tags
    Area Contact Friction
Click For Summary
SUMMARY

The discussion centers on the principle that frictional force is independent of the contact area between two surfaces, as articulated by the equation F=μN, where F represents frictional force, μ is the coefficient of friction, and N is the normal force. Participants clarify that while increased surface area may intuitively suggest greater friction due to more interlocking irregularities, the distribution of weight across a larger area actually reduces the pressure per unit area, maintaining a constant frictional force. This understanding is crucial for accurately applying friction concepts in physics and engineering.

PREREQUISITES
  • Understanding of basic physics concepts, particularly Newton's laws of motion.
  • Familiarity with the equation of friction, specifically F=μN.
  • Knowledge of surface interactions and material properties.
  • Basic grasp of pressure and its relationship to force and area.
NEXT STEPS
  • Explore the concept of pressure and its mathematical relationship with force and area.
  • Study the coefficient of friction and its dependence on material properties.
  • Investigate real-world applications of friction in engineering, such as tire design and braking systems.
  • Learn about the role of surface roughness in frictional interactions.
USEFUL FOR

Students of physics, engineers involved in material science, and anyone interested in understanding the principles of friction and surface interactions.

takando12
Messages
122
Reaction score
5
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.
 
Physics news on Phys.org
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.
 

Similar threads

High School Rolling of non-deforming sphere on a non-deforming rough surface?
  • · Replies 4 ·
Replies
4
Views
2K
Undergrad Dependence of friction on area.
  • · Replies 6 ·
Replies
6
Views
2K
High School Frictional force and surface area in contact
  • · Replies 12 ·
Replies
12
Views
5K
High School Why does ice have more friction when it's solid compared to when it's melting?
  • · Replies 11 ·
Replies
11
Views
2K
High School Vacuum surface area balance and force
  • · Replies 4 ·
Replies
4
Views
2K
High School Questions about momentum and force as well as normal force/friction
  • · Replies 35 ·
2
Replies
35
Views
5K
High School Why does an increase in surface area lead to a reduction in pressure?
  • · Replies 6 ·
Replies
6
Views
3K
High School Why does friction decrease with repeated force application?
  • · Replies 11 ·
Replies
11
Views
2K
High School Friction Independent of Area: Understand It Here
  • · Replies 10 ·
Replies
10
Views
2K
Undergrad What is the acceleration at the contact point between a wheel and surface?
  • · Replies 17 ·
Replies
17
Views
4K