thermodynamics problem

[haley5p]

1) A rigid walled tank 5m³ contains helium at 10 bar. The cylinder is heated from 10 °C to 50 ° C. What is the work done during the heating cycle.

 

 

2)An expanding gas storage vessel contains 5 m³ of methane at 1.1 bar. On a hot day the gas is heated from 20 °C to 35 °C. What work is done by the gas on its surroundings

3)

One mole of CO₂ is charged to a piston at 10 bar pressure 293K. The piston is allowed to expand to 4 times its volume isothermally. What work is done on the surroundings? The gas behaves ideally

 

A more complicated example using a polyatomic gas

Part1

• CO₂ is charged at 2 bar to a piston at 298 K volume 0.5 m³. It is known to vary as polytonic gas PV²=C. The gas is allowed to expand isothermally to twice its volume what work is done by the system

 

Part 2

• A Spring force (5 kN/m extension) is added to retain the piston what work is done this time if the expansion is the same and how much work is done against the spring the piston area is 0.1 m²

^{4)A polytonic gas which expands according to PV2=C is charged to a piston at 3 bar.The piston is allowed to move and the pressure in the cylinder drops to 0.6 bar. Calculate the work done by the system on the surroundings}

^{5)A polytonic gas which expands according to PV2=C is charged to a piston at 20 bar. The piston is allowed to expand from a volume of 0.05m3 to 0.1m3 The piston is then cooled isobarically and the volume shrinks back to its original value of 0.05m3. The piston is locked in place and the system is heated until the pressure reaches the starting pressure of 20 bar. Calculate the work done for each stage and the net work done during the total cycle}

⁶⁾

^{)An ideal gas is charged to a piston at 0.5 bar the piston is compressed isothermally to 0.1 of its original volume calculate the work done on the system by the surroundings}

⁷⁾

A piston –cylinder contains 0.05m³ of a gas initially at 200kPa. At this state a linear spring that has a spring constant of 150kN/m is touching but not exerting a force on the piston. The piston is now heated causing the piston to rise and compress the spring until the cylinder volume has doubled. The cross sectional area of the piston is 0.25m² calculate the final pressure in the cylinder and the total work done by the gas

^{please help me to solve these problems I would aprecciated so much}

^{i am so strugging with these problema!helpppppppppppppppp meeeeeee!}

 

[CaptainPanic]

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Moderator Note

haley5p,

 

Please note that this is obviously homework. You will not get any answers, unless you show what you have so far done to solve these problems. Posting only the questions is not sufficient. You are obviously doing some engineering course, not a management course, so asking other people to do your work is not going to teach you the necessary skills to pass the class.

 

Everybody,

Please do not answer any questions until our OP has shown any efforts into solving these problems.