Question

By immersing a manometer at different depths in a water tank, we obtain the following values: Depth (1) = 0.3 m, Pressure (1) = 104.24 Pa, Depth (2) = 2.1 m, Pressure (2) = 121.88 Pa. Determine the value of Earth's gravity in the experiment. (do not write units)

Answer 1

For a static fluid, P=dgh, where P is change in pressure, d is density of the fluid, g is gravitational acceleration and h is change in height.

Here,P=121.88-104.24 = 17.64 Pa, h=2.1-0.3=1.8 m, d=1000 kg/m3 (density for water)

So, 17.64 = 1000*g*1.8

=>g=17.64/(1000*1.8) = 9.8*10^-3 m/s2.

So, acceleration is 9.8*10^-3 m/s2