What Is Viscosity?

Internal friction

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Viscosity measures a fluid’s resistance to layers sliding past each other.
• Honey is thousands of times more viscous than water; air far less.
• Liquids get runnier when heated; gases get more viscous.

Steps

1. Layers sliding past layers
2. Warm syrup
3. Honey versus water
4. Shearing honey
5. Sliding over honey
6. Gases and heat