Water flows through a valve at the rate of 1000 lbm/s. the pressure just upstream of the valve is 90 psi and the pressure drop across the valve is 50 psi. the inside diameters of the valve inlet and outlet pipes are 12 and 24 in. the flow occurs in a horizontal plane. determine the loss in available energy units across the valve.

Rohit is trying to tune an instrument

As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. there is no one around to , so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. you pull up on the rope to lift the box. use g for the magnitude of the acceleration due to gravity and neglect friction forces. once you have pulled hard enough to start the box moving upward, what is the magnitude f of the upward force you must apply to the rope to start raising the box with constant velocity? express the magnitude of the force in terms of m, the mass of the box.

How to calculate voltage drop in a series circuit