QUESTION 4 During systole the pressure in the V increases and the and are open. With mitral stenosis, there is a greater than ususal pressure difference between the atrium and the QUESTION 5 What is the (assumed) velocity of the fluid at the point where the fluid touches a surface? The fluid velocity at the surface depends on the viscosity of the fluid O The velocity of the fluid must be solved for using a mass balance equation There is no relative velocity between the fluid and the surface (for a stationary plate, the fluid velocity is zero) The fluid velocity is the maximum of the quadratic fluid distribution