law of thermal dynamic

We use this applet to find the relation between temperature, pressure and volume when one of them remains constant.

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We draw conclusion that thermal dynamic can be described with pressure, volume and temperature.

We define some other thermal transfer process, which are isobaric( pressure remains constant ) and isovolume ( volume remains constant). and solve a simple problem.

We draw the curve for each thermal transfer process: isothermal, adiabatic, isobaric and isovolume.

We watch a video that when we use a heat gun to heat a string, is it gonna compress or expand. This is our prediction and the actual result. This is because of the material of the string, and this is used to upload and unload the can in our real life.

We define 4 process that the can lift engine works.

We derive the expression of the heat engine.

In the P-V diagram circle, The are enclosed by the graph is the total work done in the system. When we solve such a problem, we use W = intergral of PdV. The only thing is we need to be careful which element is constant during each process.

This is a pv diagram of a heat engine. based on the pressure and volume of each process, we can find internal energy, change of internal energy, work done by the engine and the heat gain or lose from the heat engine.

During this experiment, we record temperature, pressure and volume to make another pv diagram to figure out the change of heat, work done by system and change of internal energy.

This is the pv diagram we got from logo pro.

Based on the pv diagram and w = intergral of vat, we could find the change of internal energy, work done by the system, and heat change during each process. By Ein = 1.5PV, we could find the internal energy at the points A, B, C, and D