The pressure drop can be calculated using the formula: pressure drop = (head loss / length) * (density * gravity). In this case, the head loss is 40 ft and the length is 500 ft. Therefore, the pressure drop is (40 ft / 500 ft) * (density * gravity).
At time t = 0, the water level in tank A is 2 ft higher than the water level in tank B. We need to plot the elevation of the water in tank A as a function of time until the free surfaces in both tanks are at the same elevation.
Assuming quasisteady conditions, we can use the steady pipe flow equations to analyze the flow. It is important to note that the flow is laminar. We should neglect minor losses in our calculations.
Figure P8.18 shows the setup with tank A and tank B. The pipe connecting the two tanks has a diameter of 0.1 in and is made of galvanized iron.