Dynamic Viscosity Converter

Honey is significantly more viscous than water. While water at room temperature is about 1 cP, honey can range from 2,000 to 10,000 cP or even higher, depending on its composition and temperature. This high viscosity is why honey flows so slowly.

The viscosity of most liquids decreases significantly as temperature increases (they become 'thinner'). Conversely, the viscosity of gases usually increases slightly with temperature.

Some fluids, called non-Newtonian fluids (e.g., ketchup, blood, cornstarch mixtures), do not have a constant viscosity; their viscosity changes depending on the applied shear stress or shear rate.

One of the longest-running laboratory experiments in the world, the pitch drop experiment demonstrates the high viscosity of pitch (a derivative of tar). A drop of pitch falls from a funnel about once every decade.

Contrary to the popular myth that glass in old church windows is thicker at the bottom because it flows over centuries, glass is an amorphous solid, not a very slow-moving liquid. The variations are due to historical glass manufacturing processes.

The viscosity of motor oil is one of its most critical properties. The oil must be thin enough to flow and lubricate engine parts at cold temperatures, but thick enough to maintain a protective film at high operating temperatures.

Thixotropic fluids, like ketchup or paint, become less viscous when agitated. Rheopectic fluids are the opposite, becoming more viscous when shaken—a much rarer phenomenon.

The Earth's mantle behaves like an extremely viscous fluid over geological timescales, with a viscosity many orders of magnitude greater than pitch. This slow flow is responsible for plate tectonics.

Human blood is a non-Newtonian fluid whose viscosity is crucial for cardiovascular health. Conditions like polycythemia (too many red blood cells) can increase blood viscosity, putting strain on the heart.

These 'smart' fluids can change their viscosity dramatically when an electric field is applied. This property has potential applications in clutches, shock absorbers, and hydraulic systems.

Adding even small amounts of long-chain polymers to a solvent can drastically increase its viscosity. This principle is used to create gels, thickeners in food, and fracking fluids.

The viscosity of lava varies greatly depending on its temperature and silica content. Low-silica basaltic lava is less viscous and can flow for long distances, while high-silica rhyolitic lava is very viscous and tends to form steep-sided domes.

The Poiseuille (Pl) is an alternative name for the Pascal-second (Pa·s) in France, though it is not an official SI name. It honors the same scientist as the CGS unit, Poise.

The viscosity of magma is a key factor in determining the style of a volcanic eruption. Low-viscosity magma allows gases to escape easily, leading to effusive eruptions (lava flows), while high-viscosity magma traps gases, leading to explosive eruptions.

While the Poise is the CGS unit for dynamic viscosity, the Stokes is the CGS unit for kinematic viscosity. The two are related by the fluid's density. They are often confused but measure different properties.

Paint is a shear-thinning (thixotropic) fluid. It has high viscosity at rest so it doesn't drip off the brush, but when you apply it to a wall (applying shear stress), its viscosity decreases, allowing it to be spread smoothly.

Some non-Newtonian polymer solutions exhibit the Weissenberg effect, where the fluid climbs up a rotating rod instead of being thrown outwards by centrifugal force. This is due to normal stresses that develop in the sheared fluid.

At extremely low temperatures, certain substances like Helium-4 can become a superfluid, a state of matter with zero viscosity. A superfluid can flow without any friction and even climb up the walls of its container.