The following is an explanation of each type of friction force and its formula:
1. Kinetic frictional force
Kinetic friction occurs when two objects rub against each other and there is relative motion between the two objects. This force slows down the movement of objects and can be calculated using the formula:
F = µkN
Where:
F = Kinetic frictional force (Newtons)
µk = coefficient of kinetic friction
N = Gaia normal (Newton)
The coefficient of kinetic friction is a constant that depends on the properties of the contacting surfaces. The value of this coefficient varies depending on the type of contact surface and factors such as surface roughness, pressure and humidity. The greater the value of µk, the greater the resulting kinetic frictional force.
2. Static friction
Static friction occurs when two objects are at rest and in contact. This force allows objects to stick to other surfaces and prevents them from falling or sliding. The formula for calculating static friction is:
Fmax = µsN
Where:
Fmax = Maximum static friction force (Newtons)
µs = Coefficient of static friction
N = Gaia normal (Newton)
The coefficient of static friction is also a constant that depends on the properties of the contacting surfaces. The value of this coefficient also varies depending on the type of contact surface and factors such as surface roughness, pressure and humidity. The greater the value of µs, the greater the maximum static frictional force that can be generated.
3. Air friction
Air friction occurs when objects move through the air. This force slows down the movement of objects and can be calculated using the formula:
F = 0.5ρv^2ACd
Where:
F = Air friction (Newtons)
ρ = Density of air (kg/m^3)
v = object speed (m/s)
A = cross-sectional area of the object (m^2)
Cd = Drag coefficient (dimensional)
The drag coefficient is a constant that depends on the shape and size of the object and the speed at which the object is moving. The value of this coefficient varies depending on factors such as shape, size, surface smoothness, and speed of movement of the object. The greater the value of Cd, the greater the resulting air friction.
Using the formulas above, we can calculate the amount of friction that occurs on an object when it comes into contact with another surface or when it moves through the air.