- #1

Kushwoho44

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- TL;DR Summary
- I'm having trouble understanding intuitively the relation between the LHS and RHS of

dU = n*c_v *dT = -pdV.

Hello forumites,

I've been working with the following expression for the change in internal energy in an isentropic scenario.

$$dU = n*c_v *dT = -pdV$$

However, I'm a bit stumped here, the left hand side of the expression (or middle rather), states the change in internal energy is the product of the specific heat for constant volume and temperature, but this is equal to the work done on the system, which is the product of pressure and the volume differential.

This is confusing to me. We first invoke a constant-volume argument and then on the right hand side, state that it's equal to an expression dependent on a change in volume.

Any help would as always be appreciated.

I've been working with the following expression for the change in internal energy in an isentropic scenario.

$$dU = n*c_v *dT = -pdV$$

However, I'm a bit stumped here, the left hand side of the expression (or middle rather), states the change in internal energy is the product of the specific heat for constant volume and temperature, but this is equal to the work done on the system, which is the product of pressure and the volume differential.

This is confusing to me. We first invoke a constant-volume argument and then on the right hand side, state that it's equal to an expression dependent on a change in volume.

Any help would as always be appreciated.