In Poiseuille's method of determination of viscosity , what is the physical quantity that requires greater accuracy in measurement?Formula eta = (pi P r^4)/(8 VI)

In Poiseuille's method of determination of viscosity , what is the phy

1.	In Poiseuille's method of determination of viscosity , what is the physical quantity that requires greater accuracy in measurement?Formula eta = (pi P r^4)/(8 VI)
Answer» SOLUTION :The inner radius of the capillary tube apperars with a 4TH POWER in the equation . So if there is an error it becomes 4times . Hence inner radius must be MEASURED with high accuracy.