How do you solve the expandable gas cylinder problem with a spring?

AI Thread Summary
The discussion centers on solving a physics problem involving an expandable gas cylinder connected to a spring. The initial conditions include a pressure of 1.00 atm, a temperature of 20.0°C, and a volume of 6.00 L. The user attempts to calculate the height displacement of the piston after increasing the temperature to 503 K but arrives at an incorrect value of 0.482 m. A suggestion is made to develop the equation for pressure, incorporating the initial and final states of the gas, to correctly solve for the height. The conversation emphasizes the importance of accurately applying gas laws and pressure equations in the calculations.
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Homework Statement



An expandable cylinder has its top connected to a spring with force constant 2.00 103 N/m. (See Fig. P10.58.) The cylinder is filled with 6.00 L of gas with the spring relaxed at a pressure of 1.00 atm and a temperature of 20.0°C.


I searched for a similar question however I didnt understand it. Maybe it was the calculation error. Someone help me...

Homework Equations



PV = nRT
[PV/T]i = [PV/T]f
Volume of cylinder = Ah


The Attempt at a Solution



First I convert my units. Initial state: 101325 Pa, 293 K, and 0.006 m^3
I determined the constant by using the gas law PV/T. (101325)(0.006)/293 = 2.0749 [(Nm^2)/K].
After the temperature is increased to 503 K (273+230), the piston rises and the volume changes. The new volume is 0.006 + Ah = 0.006 + 0.01h. The pressure is equal to P = F/A. F is the force constant times dispalcement (h), which is 2000 N/m. P = 2000/0.01 = 200000h N/m^2.
Putting everything together we get
2.0749 = (200000h)(0.006+0.01h)/503

The answer h = 0.482 m or 48.2 cm is incorrect. Any suggestion or corrections. Thank you.
 

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Touchme said:

Homework Statement



An expandable cylinder has its top connected to a spring with force constant 2.00 103 N/m. (See Fig. P10.58.) The cylinder is filled with 6.00 L of gas with the spring relaxed at a pressure of 1.00 atm and a temperature of 20.0°C.I searched for a similar question however I didnt understand it. Maybe it was the calculation error. Someone help me...

Homework Equations



PV = nRT
[PV/T]i = [PV/T]f
Volume of cylinder = Ah

The Attempt at a Solution



First I convert my units. Initial state: 101325 Pa, 293 K, and 0.006 m^3
I determined the constant by using the gas law PV/T. (101325)(0.006)/293 = 2.0749 [(Nm^2)/K].
After the temperature is increased to 503 K (273+230), the piston rises and the volume changes. The new volume is 0.006 + Ah = 0.006 + 0.01h. The pressure is equal to P = F/A. F is the force constant times dispalcement (h), which is 2000 N/m. P = 2000/0.01 = 200000h N/m^2.
Putting everything together we get
2.0749 = (200000h)(0.006+0.01h)/503

The answer h = 0.482 m or 48.2 cm is incorrect. Any suggestion or corrections. Thank you.

You have to develop the equation for pressure:

P_f = P_i + kh/A = nRT_f/V_f

Since P_i = nRT_i/V_i, and V_f = V_i + Ah

you should be able to work that out for h.

AM
 
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