Newton's 3rd Law and Momentum

I checked and and briefly discussed the reading and questions from the textbook.  I emphasized that all forces come in pairs that are equal and opposite in value.  The Third Law pair for all objects can be determined fairly easily using the force naming terminology we developed in the first unit.  For example, for a book sitting on the table, we can look at the gravity force as the Force of Earth on the book.  The third law pair of this would be the Force of Book on Earth.  I also did a demonstration using the force sensors to prove that in all interactions, the forces are equal and opposite.

We then moved on to the impulse-momentum equation as it is derived from Newton's second law.  I did a demo with an egg dropping on the floor vs. begin thrown at a sheet.  In one scenario, the egg is moving slow and the egg breaks, in the other it is moving very fast, but doesn't break.  Clearly the change in momentum of the pitched egg is greater than the dropped egg, yet more force was applied on the egg that was moving slower, so it broke.  We will discuss this concept in greater detail next time.

HW:  Finish WS 5-1; WS 1 and any other class work that you didn't finish.

Energy and Heat Exam

I collected the homework packet and gave the entire period for the test.

HW:  Read chapter 5; Review Questions #1-11 AND Choose 5 Think and Explain questions

Review Day

I checked the Review Sheet and WS 4 and we whiteboarded select problems.  We also took two quizzes on the Powerhouse lab and WS 3.

HW:  Assemble HW Packet, study for test; download practice test and bring to tutorial (Monday periods 2, 4)

Heat Basics

We graded Quiz #1 and the Roller Coaster quiz, then took the quiz on WS 2b.  I stamped Worksheet 3, then gave some class time to correct it in class (WS 3 key).  If you didn't get a chance to finish the corrections, you can find the solutions here.  Also, you will need to correct your answers to the Powerhouse Lab.  There will be 2 quizzes next time, one on problem 6 on WS 3 and the other on one of the easier Power problems from the lab.

We also began our discussion of heat and heat transfer.  We took notes and calculated the temperature of a Bunsen Burner flame.

HW: WS 4 and Review Sheet; Study for quiz on WS 3 and Powerhouse Lab

Powerhouse

I checked the homework and I posted the numerical answers on the board.  I went over selected problems.  There will be a quiz on problems 1-4 next class.  You can check the full answers here (will be posted on Friday afternoon).

We took a quiz on the roller coaster problem, then learned that the energy used per unit time is power.  We then found out who the most powerful student was by completing the powerhouse lab.  If you want additional information about power, click here.

HW: Correct WS 2b- quiz next time; finish lab; WS 3

More Energy, Less Work

I checked the Roller Coaster problem for the people who had not previously gotten a stamp.  There will be a quiz on a similar problem next time.  You can check your work for the problem here.  I also discussed the idea of work, and demonstrated that an object pulled at constant velocity requires a constant amount of force, no matter how far you pull it.  The area underneath a graph of force and displacement is a rectangle, thus work can be determined by the equation W = FΔx.

I also showed the easy way to do Energy-Work problems when we assume a 100% energy transfer and there is a single energy type present in the initial and final conditions.  Homework is to finish the worksheet we started in class.

The last 30 minutes of the period we spent collecting data for the popper lab.

HW:  Finish WS 2b, finish lab, study for quiz on roller coaster problem.

Energy Bar Graphs and Roller Coaster Problem

I checked the homework.  You will need to correct it, and we will have a quiz on it next time.  We discussed energy types, how to identify what energy type is present and how to make an energy bar graph.  We completed WS 2a in class and corrected it.  The last 30 minutes of class we learned the equations for GPE and KE and completed the Roller Coaster problem.

HW: Finish roller coaster problem, correct WS 1 and study for quiz.

Debrief Spring Lab

I spent a considerable amount of time discussing the conclusion questions for the spring lab.  After the discussion, we took the quiz on the lab (it was open note/lab) and turned in the lab.  We took notes about Energy, and most specifically Elastic Potential Energy (EPE).  I gave about 25 minutes for students to work on the homework.

HW: WS 1

Begin Energy Unit and Spring Lab

We started the year off with new seats and my annual cautionary tale about second semester senioritis. We also began our unit on energy by investigating the energy stored in a spring in the Spring Lab.

HW: Finish pages 1-3 on the lab