Liquids are called Newtonian if. __ ... their coefficient of viscosity does not depend on speed ... their coefficient of viscosity is independent of temperature ... their coefficient of viscosity is constant ... their coefficient of viscosity depends on fluid velocity Online Test Pad

## Step 1<br />The problem is asking us to identify the correct statement that defines Newtonian liquids. Newtonian liquids are those that follow Newton's law of viscosity. This law states that the shear stress between adjacent layers of a fluid is proportional to the velocity gradient between the layers.<br /><br />## Step 2<br />The coefficient of viscosity is a measure of a fluid's resistance to flow. For Newtonian fluids, this coefficient is constant, meaning it does not change with the speed of the fluid.<br /><br />## Step 3<br />The other options are incorrect because they either describe non-Newtonian fluids or they are not related to the definition of Newtonian fluids.