What does viscosity measure in a liquid?

Viscosity measures the resistance to flow of a liquid. It quantifies how easily a liquid can deform and move under an applied force. A high-viscosity liquid, such as honey, flows more slowly and with greater resistance compared to a low-viscosity liquid, like water, which flows more freely. This property is crucial in refrigeration systems, as it affects the efficiency of the refrigerant and the overall performance of the system. Understanding viscosity helps in selecting the appropriate lubricants and fluids for various components, ensuring optimal operation and energy efficiency in refrigeration processes.