Three ways to reduce it
Three standard ways, and each attacks friction through one of the factors section 5.3 identified.
1. Smoothing the surfaces
Reducing the roughness of the contact surfaces — polishing, planing, machining them smooth. This works directly on the nature of the surfaces, the factor activity 02 tested.
2. Lubricants
Applying a lubricant such as graphite, thin oil or grease between the two contact surfaces. The lubricant keeps a thin layer between the surfaces so that they no longer rub directly against each other.
3. Balls that roll
Placing balls between the two rubbing surfaces in such a way that they can roll. Putting balls in this way prevents the two surfaces from rubbing against each other.
Ball bearings
The ball bearings used in many machines and vehicles, where a rotating part is fixed to a non-rotating axle rod, are made in exactly this way.
Figure to be added
| Method | What it changes |
|---|---|
| Smoothing | Makes the surfaces less rough |
| Lubricants | Separates the surfaces so they do not touch directly |
| Bearings | Replaces sliding with rolling |