How does an increase in temperature generally affect the viscosity of a fluid?

An increase in temperature decreases the viscosity of a fluid, allowing it to flow more easily. This phenomenon occurs because as temperature rises, the kinetic energy of the fluid's molecules increases, causing them to move faster and collide with each other more frequently. This heightened movement helps to overcome the intermolecular forces that create viscosity, enabling the fluid to flow with less resistance.

For example, when you heat a cooking oil, it becomes less viscous and pours more readily than when it is cold. The inverse relationship between temperature and viscosity is a fundamental concept in fluid dynamics that applies to many common liquids, whether they are oils, water, or other types of fluids.