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Themodynamic Processes | Lecture 2 | PV diagrams, Processes

Themodynamic Processes | Lecture 2 | PV diagrams, Processes

Some experiments using thermodynamics

Learning Objectives

One of Project BoxSand's goals is to close-the-loop on effective curriculum reform iterations. We are coding all the content and resources, every text, video, and homework question, to a set of atomistic learning objectives. As students go through the course we can see how their path through resources relates to successfully completing these learning objectives. This allows us to find the most effective resources for accomplishing the desired learning outcomes.  

Summary

The goal is to become familiar with the characteristics of vectors in multiple representations and use them for the appropriate physical quantities. Specifically, students need to be able to use physical and mathematical representation to perform vector operations such as scalar multiplication, addition, subtraction.

 

Atomistic Goals

Students will be able to...

1. Understand how the first law relates to PV cycles.
2. Understand what a complete cycle is.
3. Understand the different types of thermodynamic processes: isobaric, isochoric, isothermal, adiabatic.
4. Know how to calculate the pressure or temperature at a given point on a P-V diagram

Pre-lecture | Familiarize Stage

The success of this curriculum relies heavily on preparing for lecture by engaging with the pre-lecture study resources below. The pre-lecture videos and homework have the strongest correlation with success, followed by the reading. More engagement with all of the resources is correlated with better performance in the course. Students who do the pre-lecture study and homework also report much greater satisfaction with the course. Routine is the heavy lifter of success!

Reading

To prepare for the pre-lecture homework and the lecture material, read the following OpenStax textbook chapters, BoxSand introductions, or other linked articles. 

PV-diagrams are introduced in chapter 15.2 of the Openstax text book.

Openstax College Textbook Icon

 

Videos

To prepare for the pre-lecture homework and lecture materials, watch the following required videos. Research shows that taking notes by hand is the preferable method for retention. For this reason these videos are paced so that you can write down everything we write down. There are also supplementary videos that are strongly suggested but could be viewed after lecture while working on practice problems. Watching all of these videos is shown to be one of the strongest correlators with success in this course. 

| Required Pre-lecture Videos |

ideal gas processes isochoric(3min)

Kaltura URL

ideal gas processes isobaric(2min)

Kaltura URL

ideal gas processes isothermal(3min)

Kaltura URL

ideal gas processes adiabatic(3min)

Kaltura URL

ideal gas processes work and heat signs (6min)

Kaltura URL

| Supplemental but Suggested |

Ideal gas processes overview(3min) **

Kaltura URL

work gas expansion compression(5min) **

Kaltura URL

   

Simulations

 

Other Suggested Resources

 

Pre-lecture Homework

Complete the following assignment before attending lecture or answering the lecture questions. Watching the videos and performing the suggested reading before attempting these questions will likely be necessary.

    Pre-lecture Homework | Calendar

 

Lecture | Foundation Stage

In order to maximize efficiency while learning physics, education research has suggested a Flipped Classroom approach with multiple Guided Peer Learning (GPL) lectures a week. To get the most out of these events students need to front load the lecture with pre-lecture study, outlined above. Attending a live lecture is highly preferred but if you're unable to, there is an asynchronous alternative. During lecture it is important to either use a digital version with a tablet and pen, or print a copy to write on. If the live lectures feel too fast, read through each lecture question and prepare before class begins. Many questions will be skipped due to time constraints, it is a good study strategy to come back and try to answer those questions.

 

Lecture Templates

The blank template workbook is provided so that you do not have to write down the questions or redraw complicated figures.

    Lecture Template | Calendar

Lecture Solutions

The completed templates will be available within one week of the last lecture class. It is an important metacognative step to review the questions you've answered that we were unable to cover in class.

    Lecture Solutions | Calendar

Post-lecture | Practice Stage

The most important post-lecture activity is doing your post-lecture homework shortly after completing the lecture questions. You learn physics by practicing problems! Occasionally there may be additional resources on the BoxSand site that we feel could be helpful in your learning. Those resources will be linked here.

 

Reading

    1. none

Videos

    1. none

Simulations

    1. none

Other Suggested Resources

    1. none

Example Problems and Practice

1. (a) and (b): which type of thermodynamic process is sketched? (c) Sketch the thermodynamic process in which temperature does not change. (d) Sketch the thermodynamic process in which heat neither enters or nor leaves the system.

This is an image of two P.V. diagrams. The first P.V. diagram labeled as A shows an initial point with an initial pressure and a low initial volume and a final point with the same pressure and a higher final volume. The second P.V. diagram labeled as B shows an initial point with a high initial pressure and initial volume and a low final pressure and the same volume.

2. During a thermodynamic process, the pressure in a container goes to $\frac{2}{3}$ it's original pressure: $P_f = \frac{2}{3} P_i$. Likewise, $T_f = 2T_i$. (a) What is the final volume (in terms of $V_i$)? (b) Is $\Delta E$ for this process positive or negative? (c) Does heat enter or leave the system during this process, and if so, in which direction does heat flow?

3. Using the diagram below, find the following: (a) the temperature $T_1$ at point 1 and the pressure $P_3$ at point 3. (B) For each step of the process - from points 1 to 2 and from points 2 to 3 - was the change in thermal energy positive or negative? The work? Did heat enter or leave the system during this stage, and how much? Hint: make a table.

Solutions

There are additional practice problems you can work for credit | Calendar

 

Post-lecture Homework

Complete the post-lecture homework assignment as soon as possible after completing the lecture questions. If you need help, and you've already watched the pre-lecture videos and read the pre-lecture readings, reach out to one of our many support systems available here: support site.

    Post-lecture Homework | Calendar

Challenge Homework | Mastery Stage

One of the main learning objectives is improving problem solving and critical thinking skills. These are high on Bloom's Taxonomy of thinking and require synthesizing multiple logical ideas and concepts into a consistent framework. To improve these skills requires continually pushing the envelope on what you can analyze. Challenge homework is designed to push you, often to the point of reaching out for help. Luckily we are ready to support you with our live and asynchronous support. The last objective of challenge homework is for you to write out your solutions clearly, have them graded by a human, and partial credit given. Exams are all about partial credit and a clearly organized solution that leads the reader through the logical pieces. Challenge homework is place to practice these steps. For more help on any studies or homework, see our support site.

Your challenge homework solutions are to be saved as a PDF and uploaded to Gradescope.

Challenge Homework Questions

Download the questions below and either answer them digitally with your tablet and pen or by hand.

    Challenge Homework Questions can be found on the calendar.

Challenge Homework Solutions

Challenge homework solutions will be available within one week of their due date.

   Challenge Homework Solutions | Calendar