# Free Friction Coefficient Calculator

## Calculate the friction force using the force of friction equation.

##### Structure inputs
Vertical force kN
Enter a number greater than 0
Coefficient of friction
Enter a number greater than 0 and less than 1

##### Results
Friction resistance kN

## What is the force of friction equation?

The force of friction is a resistive force that opposes the relative motion or tendency of motion between two surfaces in contact. The equation for the force of friction depends on the nature of the surfaces and can be expressed in two general forms: static friction and kinetic friction.
Fstatic = μstatic × N
Where Fstatic is the frictional force
μstatic is the coefficient of friction
N is the normal force

## How to find force of friction?

To find the force of friction between two surfaces, you need to know the type of friction involved (static or kinetic) and the coefficient of friction for the specific materials in contact. The coefficient of friction is a dimensionless constant that represents the frictional properties of the surfaces.
Here are the steps to find the force of friction:
Step 1: Identify the type of friction: Determine whether the surfaces are at rest relative to each other (static friction) or are in motion relative to each other (kinetic friction). If the surfaces are stationary, you need to calculate the static friction. If they are moving relative to each other, you need to calculate the kinetic friction.
Step 2: Determine the coefficient of friction: The coefficient of friction depends on the materials in contact. It can be found in reference materials or through experimentation. The coefficient of static friction and the coefficient of kinetic friction.
Step 3: Calculate the normal force (N): The normal force is the force exerted by a surface to support the weight of an object pressing against it perpendicular to the surface. For example, if an object is resting on a horizontal surface, the normal force is equal to the object's weight. If the object is on an inclined plane, the normal force will be less than the weight.
Step 4: Calculate the force of friction using the equation above.

## How do you measure the coefficient of friction?

The coefficient of friction is a dimensionless quantity that represents the ratio of the force of friction between two surfaces to the normal force pressing them together. There are several methods to measure the coefficient of friction, and the choice of method depends on the specific situation and the materials involved.
One of the most common methods is the Sliding Friction Method. This method measures the force required to slide one object over another. The basic setup involves placing the two surfaces in contact and applying a known force to one of them, gradually increasing it until the object starts to slide. By measuring the force applied and the normal force (perpendicular force pressing the surfaces together), you can calculate the coefficient of friction using the formula: Coefficient of Friction = Frictional Force / Normal Force.
Another common method is the inclined Plane Method. In this method, the two surfaces are placed on an inclined plane, and the angle of inclination is adjusted until the object starts to slide down the plane. The coefficient of friction can be calculated using the formula: Coefficient of Friction = tan(angle of inclination).

## What are the SI units of friction?

Friction is a force and is measured in the International System of Units (SI) in Newtons (N). The SI unit for friction is the same as the unit for force, which is the Newton (N). Friction is the force that opposes the relative motion or tendency of such motion of two surfaces in contact. When two surfaces slide against each other or attempt to slide against each other, friction acts to resist their motion, and the amount of friction force can be measured in Newtons.

## What are the 4 types of friction?

Friction is the force that opposes the relative motion or tendency of such motion of two surfaces in contact. There are four main types of friction:
• Static Friction: This type of friction occurs between two surfaces that are in contact but not sliding past each other. It prevents the object from starting to move when a force is applied to it. For example, when you try to push a heavy box and it doesn't move, the static friction is at play.
• Kinetic Friction: Also known as dynamic friction, this type of friction occurs when two surfaces are in motion relative to each other. It opposes the motion and makes it harder to keep an object moving at a constant velocity. For instance, when you push a box across the floor, kinetic friction slows it down.
• Rolling Friction: This type of friction occurs when a round object, like a wheel or a ball, rolls over a surface. It is generally smaller than kinetic friction, making it more efficient for transportation. Rolling friction is why wheels are commonly used in various forms of transportation.
• Fluid Friction: Also known as viscous friction, this type of friction occurs when an object moves through a fluid, such as air or water. Fluid friction opposes the object's motion, making it experience resistance as it moves through the fluid. For example, when you swim or drive a car, fluid friction affects your movement.
What's this calculator used for?
This free calculator helps calculate force of friction using the force of friction equation. Static friction is calculated using the coefficient of friction and normal force. Use common friction coefficients for different materials to calculate a static friction force. We explain the theory on how to find frictional force.