No. This is not the work. This is the change in internal energy. To get the work, you need to integrate PdV.ZLing said:Homework Statement
Nitrogen at 100°C and 600 kPa expands in such a way it can be approximated by a polytropic process with n=1.2. Calculate the work and the heat transfer if the final pressure is 100 kPa.
Homework Equations
The Attempt at a Solution
I used the equation T2/T1=(P2/P1)^[(n-1)/n] to find T2. Then i used W=nCv(T1-T2) to calculate work done. Is this correct?
If you know the change in internal energy and the work, then you can use the first law to get the heat.But i don't know how to calculate the heat transfer.
Hi, does that mean I have to find V1 and V2 first?Chestermiller said:No. This is not the work. This is the change in internal energy. To get the work, you need to integrate PdV.
If you know the change in internal energy and the work, then you can use the first law to get the heat.
Chet
That's one way to start.ZLing said:Hi, does that mean I have to find V1 and V2 first?
A polytropic process of nitrogen is a thermodynamic process in which the gas undergoes a change in its pressure and volume while following a specific equation known as the polytropic law. This equation relates the pressure and volume of a gas undergoing a reversible process.
The polytropic law for nitrogen is represented by the equation P1V1^n = P2V2^n, where P1 and V1 are the initial pressure and volume, P2 and V2 are the final pressure and volume, and n is the polytropic index. This index can vary from 0 to ∞ and represents the type of process (isothermal, adiabatic, isobaric, etc).
A polytropic process of nitrogen differs from other thermodynamic processes in that it follows a specific equation, the polytropic law, and can have a variable polytropic index. This allows for a more accurate representation of the process, as it takes into account the specific conditions of the system.
The polytropic process of nitrogen has many applications in various industries, such as in gas turbines, refrigeration systems, and air compressors. It is also used in the production and storage of liquid nitrogen, as well as in the study of gas dynamics and thermodynamics.
The polytropic process of nitrogen is related to the ideal gas law, as it is a specific case of this law. The ideal gas law states that the pressure, volume, and temperature of an ideal gas are related by the equation PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the universal gas constant, and T is temperature. The polytropic law is a variation of this equation, taking into account the polytropic index.