Which statement best defines viscosity?

Which statement best defines viscosity?

• A. The shiny appearance of a metal
• B. How hot a substance gets when burned
• C. Measure of how easily a substance flows
• D. The mass of a substance

Answer: (C)

Viscosity describes how much a liquid resists flowing, a measure of the internal friction as molecules move past each other. High viscosity means thick, slow-flowing liquids (like honey), while low viscosity means thin, fast-flowing ones (like water). This is about flow behavior, not about shine, how hot something gets when burned, or its mass. Temperature affects viscosity: heating generally lowers it, since molecules move faster and slide past each other more easily. This helps explain everyday observations, such as why syrup pours slowly when cold and why oil’s flow changes with temperature.

Viscosity describes how much a liquid resists flowing, a measure of the internal friction as molecules move past each other. High viscosity means thick, slow-flowing liquids (like honey), while low viscosity means thin, fast-flowing ones (like water). This is about flow behavior, not about shine, how hot something gets when burned, or its mass. Temperature affects viscosity: heating generally lowers it, since molecules move faster and slide past each other more easily. This helps explain everyday observations, such as why syrup pours slowly when cold and why oil’s flow changes with temperature.