Problem 2: Water is flowing smoothly through a closed pipe system. At one point the speed of water is 3 ms-1, while at another point 3 meters higher the speed is 4 ms-1. At the lower point, the pressure is 80 K Pa. Find the pressure at the upper point. Where 1 Nm-2 = 1 Pa.
Given data At the upper point
Speed of water = v1 = 4 ms-1, (Relative) Height, h1 = 3 m
At the lower point
Speed of water = v2 = 3 ms-1, Pressure = P2 = 80 K Pa = 80000 Pa
Relative height = h2 = 0 m
Required Pressure at the higher point = P2 =?
Formula For the smooth flow of water, the Bernoulli’s equation is
Put the values
Now we know that density of water is 1000 kg m-3 and the gravitational acceleration is 9.8 ms-2. Therefore,