Friction Calculator
Calculate friction force, coefficient of friction, or normal force using physics formulas
Calculate Friction Force
Force perpendicular to the surface
Dimensionless value (typically 0.01 - 1.5)
Friction Calculation Results
Formula used: F = μ × N
Where: F = Friction force, μ = Coefficient of friction, N = Normal force
Friction Analysis
Example Calculation
Car Braking Example
Scenario: A 1500 kg car braking on dry concrete
Normal force: Weight = 1500 kg × 9.81 m/s² = 14,715 N
Coefficient of friction: μ = 0.8 (rubber on dry concrete)
Calculation
F = μ × N
F = 0.8 × 14,715 N
F = 11,772 N
This is the maximum friction force available for braking.
Common Friction Coefficients
Steel on Steel (dry)
Steel on Steel (lubricated)
Rubber on Concrete (dry)
Rubber on Concrete (wet)
Wood on Wood
Ice on Ice
Glass on Glass
Teflon on Teflon
Types of Friction
Static Friction
Prevents motion between stationary surfaces
Kinetic Friction
Acts on moving objects (usually lower than static)
Rolling Friction
Between rolling objects and surfaces
Fluid Friction
Drag force in liquids and gases
Friction Tips
Static friction is usually higher than kinetic friction
Friction is independent of contact area
Friction is proportional to normal force
Lubrication reduces friction coefficient
Understanding Friction Force
What is Friction?
Friction is a force that opposes motion between two surfaces in contact. It arises from the microscopic irregularities and adhesive forces between surface molecules. Friction is essential for everyday activities like walking, driving, and holding objects.
Why is Friction Important?
- •Enables movement and stopping in vehicles
- •Allows humans and animals to walk
- •Essential for gripping and holding objects
- •Critical in mechanical design and engineering
Friction Force Formula
F = μ × N
- F: Friction force (Newtons)
- μ: Coefficient of friction (dimensionless)
- N: Normal force (Newtons)
Note: The coefficient of friction depends on the materials and surface conditions.
Laws of Friction
- 1.Friction is proportional to the normal force
- 2.Friction is independent of the contact area
- 3.Static friction is greater than kinetic friction
- 4.Friction depends on the nature of surfaces
Static vs Kinetic Friction
Static Friction
- • Acts when objects are at rest
- • Prevents objects from starting to move
- • Maximum value: μₛ × N
- • Usually higher than kinetic friction
Kinetic Friction
- • Acts when objects are moving
- • Opposes the direction of motion
- • Constant value: μₖ × N
- • Usually lower than static friction
Applications
Transportation
Car brakes, tire traction, train wheels
Sports
Shoe grip, rock climbing, skiing
Engineering
Machine bearings, clutches, fasteners
Daily Life
Walking, writing, opening jars