Question

pressure A vertical piston cylinder device contains a gas at an unknown pressure. If the outside pressure is 100 kPa, determine (a) the pressure of the gas if the piston has an area of 0.2 m2 and a mass of 20kg. Assume g = 9.81 m/s2. (b) What-if Scenario: What would the pressure be if the orientation of the device were changed and it were now upside down

Answer 1

Step-by-step explanation:

When Cylinder is vertical Let gas pressure inside is
`P_1` and atmospheric Pressure be

`P_0=100 KPa`

Area of Piston
`A=0.2 m^2`

mass of Piston
`m=20 kg`

from FBD

`mg+P_0A=P_1A`

`P_1=P_0+(mg)/(A)`

`P_1=100+(20* 9.8)/(0.2)`

`P_1=100+0.98`

`P_1=100.98 KPa`

(b)If cylinder is upside down

From FBD

`mg+P_2A=P_0A`

`P_2=-(mg)/(A)+P_0`

`P_2=100-(20* 9.8)/(0.2)`

`P_2=100-0.98=99.02 KPa`