Consider the unsteady flow of a fluid in the x direction through a control volume. The linear momentum of the fluid within the control volume is a function of time given by 200ti slug*ft/s, where t is in seconds and i is a unit vector in the x direction. Measurements indicate that to cause this flow the force acting on the contents of the control volume is 40i lb. Determine the net rate of flow of linear momentum through the control surface.