How is an oil's viscosity affected by heating?

Heating an oil leads to a decrease in its viscosity. Viscosity is a measure of a fluid's resistance to flow; in simpler terms, it describes how thick or thin a liquid is. When oil is heated, the kinetic energy of the molecules increases, causing them to move more freely and reducing the internal friction between the molecules. This reduction in internal friction results in the oil becoming less viscous, allowing it to flow more easily.

Understanding this principle is important in various applications, such as in the operation of engines or machinery where oil circulates and lubricates moving parts. If the viscosity of the oil decreases, it can lead to better lubrication and improved performance in machinery at higher temperatures.