Problem 7.1 A real-valued signal xx() is known to be uniquely determined by its samples when the sampling frequency is =10,000. For what values of ω is ( ) guaranteed to be zero? Please note that frequency can be positive and negative

Amixture of slurry and mud is to be pumped through a horizontal pipe of diameter 500 mm. the fluid behaves as a bingham plastic with a yield stress of 30 pa and viscosity 0.04 pa.s. describe the effects of the shear stress through a transverse section of the pipe by plotting the variation in shear stress and velocity profile: (i) just before the slurry starts to move (ii) as the slurry flows when the pressure gradient is double that in part (i)