Friction Formula
The classic Amontons-Coulomb law of friction is given by:
Ff = μ · N
- Ff: Friction Force
- μ: Coefficient of Friction (dimensionless)
- N: Normal Force (perpendicular to surface)
Dry Friction Calculator
Dry Friction - Perform scientific calculations with precision and accuracy.
Dry Friction Calculator
Dry Friction Calculator
Calculate friction force (Ff), normal force, and the coefficient of friction (μ) for mechanics and physics.
Typical Coefficients (μ)
Materials
Static
Kinetic
Rubber on Concrete
1.0
0.8
Steel on Steel (Dry)
0.8
0.6
Wood on Wood
0.5
0.3
Ice on Ice
0.1
0.03
Teflon on Teflon
0.04
0.04
Understanding Dry Friction
Dry friction is the force that opposes the relative motion of two solid surfaces in contact. It is generally independent of the area of contact but proportional to the normal force.
Static vs. Kinetic
- Static Friction (μs): The force that keeps an object at rest. It must be overcome to start motion. Usually higher than kinetic friction.
- Kinetic Friction (μk): The force acting on an object already in motion. It is generally constant for a given pair of surfaces.
Dry Friction Calculator Guide
Dry Friction
Dry (Coulomb) friction opposes motion between solid surfaces in contact. Force magnitude depends on the normal force and a coefficient of friction.
Formulas
- Static: F_s ≤ μ_s N
- Kinetic: F_k = μ_k N
Example
With μ_k=0.25 and N=120 N: F_k = 0.25 × 120 = 30 N.
FAQs
Static vs kinetic?
Static holds objects at rest; kinetic applies during sliding.
Surface effects?
μ depends on materials, roughness, and lubrication.
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