Multiple choice general knowledge science & technology viscous force is directly proportional to Mass gradient Temperature gradient velocity gradient charge gradient Reveal answer Fill a bubble to check yourself C Correct answer Explanation In fluid mechanics, viscous force follows Newton's law of viscosity: F = ηA(dv/dy), where η is viscosity, A is area, and dv/dy is the velocity gradient perpendicular to flow. It's independent of mass, temperature, or charge gradients.