Pressure on a piston in a cylinder

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SUMMARY

The pressure inside a vertical cylinder with a frictionless piston, given a cross-sectional area of 0.25 m², a piston mass of 22 kg, and an ideal gas at 310 K, is calculated using the formula Pressure = F/Area. The force is derived from the weight of the piston (22 kg x 9.8 m/s²), resulting in a pressure of 1.02 x 10⁵ Pa when atmospheric pressure is included. The volume of the gas is determined using the ideal gas law PV = nRT, yielding a volume of 0.025 m³, which corresponds to a piston height of 0.1 m or 10 cm.

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Jimkatz809
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Homework Statement



A vertical cylinder of cross-sectional area 0.25 m2 is fitted with a tight-fitting, frictionless piston of mass 22 kg. The acceleration of gravity is 9.8 m/s2 . If there are 1 mol of an ideal gas in the cylinder at 310 K, find the pressure inside the cylinder. Assume that the system is in equilibrium. Answer in units of Pa. At what height will the piston be in equilibrium under its own weight? Answer in units of m.

Homework Equations


Pressure=F/Area
PV=nRT
Height= Volume /Area



The Attempt at a Solution


Pressure =F/Area (22kg x 9.8m/s^2)/(0.25m^2) Then I added atmospheric pressure to this pressure which is 1.013x10^5 Pa. I got an answer for pressure as 1.02x10^5 Pa and I got it correct.
Then for volume I have been trying V= (1 mol x 8.3145 x 310 K)/(1.02x10^5) and I get .025 as my volume but I think this number is off and I can't figure out why... I don't want to move forward until I figure this part out.
 
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.025 looks good to me.
 
The volume is correct, in m^3. The question asks for the height, which is .025/.25 = .1 m or 10 cm. What is the answer you are given?

AM
 
I the calculations as you said and got .1 m just as you said and I tried puting it into the UTexas system but its said that is wrong. I don't understand because it makes no sense that should be the answer.
 
Jimkatz809 said:
I the calculations as you said and got .1 m just as you said and I tried puting it into the UTexas system but its said that is wrong. I don't understand because it makes no sense that should be the answer.
Try .10 m (two sig. figures).

AM
 

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