Is the magnetic field B→. a state function and exact differential?

johankep
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Homework Statement
. a state function and exact differential?
Relevant Equations
state functions
is the magnetic field B→. a state function and exact differential?

I argued that it's a state function, what do you guys think
 
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johankep said:
Homework Statement:: . a state function and exact differential?
Relevant Equations:: state functions

is the magnetic field B→. a state function and exact differential?

I argued that it's a state function, what do you guys think
I'm not sure if it makes sense to distinguish between state functions and non-state functions outside the field of thermodynamics.
How did you argue that B is a state function.

However, E is an exact differential in electrostatics since it is the gradient of a scalar field.
B is not the gradient of a scalar field.
 
Philip Koeck said:
I'm not sure if it makes sense to distinguish between state functions and non-state functions outside the field of thermodynamics.
How did you argue that B is a state function.

However, E is an exact differential in electrostatics since it is the gradient of a scalar field.
B is not the gradient of a scalar field.

Thanks for the reply Philip
regarding your question, this is the context of B here
https://en.wikipedia.org/wiki/Magnetic_Thermodynamic_Systems

 
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Philip Koeck said:
I'm not sure if it makes sense to distinguish between state functions and non-state functions outside the field of thermodynamics.
How did you argue that B is a state function.

However, E is an exact differential in electrostatics since it is the gradient of a scalar field.
B is not the gradient of a scalar field.
Sorry forget to say..my argument was that since B can be measured knowing its current value(state) only..then it's a state function but I'm not sure to be honest if my reasoning correct
 
johankep said:
Thanks for the reply Philip
regarding your question, this is the context of B here
https://en.wikipedia.org/wiki/Magnetic_Thermodynamic_Systems
Now I see why you ask. In a thermodynamic context I guess it can be important whether B is a state function or not.
I don't understand very much about this, I'm afraid, but I'm a bit surprised about the equations in the wikipedia article.
In the second equation p dV is not integrated, whereas the other 3 terms are. Probably just a typo.
What worries me more is the last term which contains both a ΔB and a dV in the integrand. Is that really correct? Do you have a derivation? Maybe it should say B rather than ΔB.
B is not an extensive quantity, so I wouldn't expect it to show up as a difference or differential in the fundamental equation.
Then the integration over V is also strange. Which V? V is one of the quantities that changes.
 
Philip Koeck said:
Now I see why you ask. In a thermodynamic context I guess it can be important whether B is a state function or not.
I don't understand very much about this, I'm afraid, but I'm a bit surprised about the equations in the wikipedia article.
In the second equation p dV is not integrated, whereas the other 3 terms are. Probably just a typo.
What worries me more is the last term which contains both a ΔB and a dV in the integrand. Is that really correct? Do you have a derivation? Maybe it should say B rather than ΔB.
B is not an extensive quantity, so I wouldn't expect it to show up as a difference or differential in the fundamental equation.
Then the integration over V is also strange. Which V? V is one of the quantities that changes.

I asked a professor his answer was "B and E are thermodynamic parameters, measurable macroscopic quantities associated to the system therefore they are state functions"... I don't think I fully understand his answer.. but yeah this is it
 
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