Download week six

**In Class Activity Plan**

**120 min – Investigating Energy Conservation** (Word, Pdf)

PURPOSE: Introduce equations for E_{g} and E_{k}, opportunity to design experiment

*Teaching Notes:*

- You should whiteboard after the first page (making pie charts).

– Goals here will be to push them towards the answers to the questions on page 2.

– Suggest energy at the top should be proportional to both mass and height.

- For many students this will be the first time they have ever had to design their own experiment. So this lab will both take a long time, and be difficult for some students.

– The proposal must have a model associated with it, and must identify what measures are going to be made and how the data is going to be analyzed.

– Also, the teacher must be very good at evaluating experiments on the fly. They may think of things that would work, but we haven’t thought of before.

- Possible experiments:

– Drop the ball from different heights and record the speed at the bottom. They can then make a graph of E_{Ig} and E_{k} and get a linear fit.

– Also a possibility of rolling things on rails and measuring speeds.

**20 min – Whiteboard – Investigating Energy Conservation
**PURPOSE: Share experimental designs and results for equations for E

_{g}and E

_{k}

Video Example: (Whiteboarding)

- What did you learn?
- What rules can you make?
- What questions do you still have?

**45 min – Board Meeting
**PURPOSE: Compare experimental designs and results for E

_{g}and E

_{k}, reach consensus about how to calculate Energies.

Video Examples: (Discussion 1, Discussion 2, Discussion 3)

- Need to define system (Schema)
- Use pie charts to help you determine what needs to be measured
- Strategy 1

– E_{Igo} – E_{Igf}

– Plot E_{k} vs. v

– Fit a curve in Excel

- Strategy 2

– E_{Igo} = ma_{g}h

– E_{kf} = m (Dv/Dt)( ½a_{g}(Dt^{2}))

– E_{kf} = m (Dv/Dt)( ½(Dv/Dt)(Dt^{2}))

– E_{k} = ½mv^{2
}– Must be supported by data!

- Energy Pie Charts are a representation of the Equation of Everything (energy conservation)

**20 min – Whiteboard – 1-d problem using both kinematics and energy conservation
**PURPOSE: Compare and contrast strategies for making calculations on constant a model using kinematics and energy;

*Problem:*

Cubs fan throws his hat straight into the air at 7m/s.

**10 min – Board Meeting
**PURPOSE: Show how basic constant a models obey energy conservation and give same results.

Emphasize energy as an easy approach that works well in some situations.

**60 min – Whiteboard – Redo 2-d problems they’ve already done now using energy &/or additional problems**

*Energy Pie Chart Problems (**Word**, **Pdf**)
Energy Problems for Practice (*

*Word*

*,*

*)*

Video Examples: (Whiteboarding 2, Discussion 4)

Note: These are often done, but not discussed in a board meeting since they have done them previously.