Type II fluids exhibit what at high speeds that reduces viscosity and allows them to flow off?

Type II fluids exhibit what at high speeds that reduces viscosity and allows them to flow off?

• A. Shear stress
• B. Temperature
• C. Density
• D. Surface tension

Answer: (A)

Type II fluids are non-Newtonian and show shear-thinning behavior: their viscosity decreases as the rate of deformation (shear rate) increases. When speeds are high, the flow imposes large shear stresses on the fluid, causing its internal structure to reorient and resist less, so the apparent viscosity drops. That reduction lets the fluid flow off surfaces more readily. Temperature, density, and surface tension aren’t the primary factors driving this rapid flow-off under high-speed conditions—the key is how viscosity changes with increasing shear (driven by higher shear stress).

Type II fluids are non-Newtonian and show shear-thinning behavior: their viscosity decreases as the rate of deformation (shear rate) increases. When speeds are high, the flow imposes large shear stresses on the fluid, causing its internal structure to reorient and resist less, so the apparent viscosity drops. That reduction lets the fluid flow off surfaces more readily. Temperature, density, and surface tension aren’t the primary factors driving this rapid flow-off under high-speed conditions—the key is how viscosity changes with increasing shear (driven by higher shear stress).