Question

A 2.5 m tall steel cylinder has a cross sectional area of 1.5 mA 2 EA. At the bottom with a height of 0.5 m is liquid water and on top of which is a 1 m high layer of gasoline (rhogasoline= 925kg/m3 ). The gasoline surface is exposed to atmospheric air at 101 kPa. Sketch the arrangement. Where is the pressure highest in the water (indicate in the sketch), and what is the value of the absolute pressure?

Answer 1

Answer:

124 kPa

Explanation:

The highest pressure in the water is in the bottom of the cylinder. The reason is because all the weight of the water and the gasoline puts some pressure plus the atmospheric air. So, the absolute pressure would be the one exerted by the atmosphere, the gasoline and the water and is calculated as follows:

$P=P_{atm}+P_{gas}+P{water}\\P=110 000Pa +1.0m*9.8m/s^2*925kg/m^3+0.5m*1000kg/m^3*9.8m/s^2\\P=123974Pa$≈124 kPa