1. livestream

2. Unit 4 Energy Notes

3. introductory discussion of energy using rubber band and spring

4. students complete Pivot Interactives: Spring Force Scaffolded

5. review for Wednesday's Unit 3 exam

6. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. discussed results from Pivot Interactives: Spring Force Scaffolded Lab (post-lab)...defined slope of F vs. x graph as spring constant...associated area of F vs. x graph as stored energy in the spring...showed stored energy could be determined by Uel = 1/2 k x^2

4. reviewed main new topics for Wednesday's Unit 3 exam

5. discussed solutions to MC section of Unit 2 exam

6. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. finished discussing solutions to MC section of Unit 2 exam

4. students took Unit 3 Exam

5. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. we will begin today's class w/ a video of me doing an experiment and then work through some notes on calculating energy.

4. reviewed post-lab discussion of spring lab

5. began discussion of energy with Feynman audio lecture found here

6. discussed other locations where energy can be stored: Uel, Ug, Uk, etc.

7. discussed 7 super simple examples of energy calculations

8. discussed pie charts (conservation of energy representational tool)

9. discussed two more involved conservation of energy examples (introduced bar charts)

10. Today's recording

1. livestream

2. Unit 4 Energy Notes

3. finished discussing pie charts (conservation of energy representational tool)

4. discussed two more involved conservation of energy examples (introduced bar charts)

5. discussed how energy is the area of the F vs. x graph

6. introduced the concept of work and the dot product

7. worked dot product examples

8. Today's recording

1. livestream

2. Unit 4 Energy Notes

3. reviewed the concept of work and the dot product

4. worked dot product examples

5. students work through prelab video for Rainforest Lab

6. students direct Mr. Spencer to determine m and also how to measure h

7. created Graphical Analysis graph of theoretical prediction and experimental prediction...actual data collection tomorrow

8. Today's recording

1. livestream

2. Unit 4 Energy Notes

3. continued working dot product examples

4. students work through prelab video for Rainforest Lab

5. students direct Mr. Spencer to determine m and also how to measure h

6. created Graphical Analysis graph of theoretical prediction and experimental prediction...actual data collection today also

7. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. students worked through several iterations of a homework quiz based on a homework problem

4. began working dot product examples for physical situations

5. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. continued working dot product examples for physical situations

4. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. continued working dot product examples for physical situations

4. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. worked an example work calculation with a force proportional to e^(-1/2)

4. showed that the work a Hookean spring does in stretching a spring is equal to the elastic energy stored in the spring

5. reviewed how the area of the v vs. t graph is equal to the integral for a function v(t)=5t

6. reviewed the W=(delta)K relationship where W=(F) dot (x) or W=int (F(x)dx)

7. discussed the work done by a Hookean and non-Hookean spring

8. worked a tremendous example where a block is dropped onto a spring (the constant weight force did positive work while the spring force did negative work and had to be determined using an integral)

9. students worked on a pendulum problem to determine the speed of the pendulum at two different positions (required conservation of energy considerations)

10. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. pop quiz on conservation of energy

4. discussed solution to pop quiz

5. discussed complete solution to M9

6. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. discussed ice flake problem

4. discussed three cases in which conservation of energy OR forces could be used:

• Case 1 - drop an object from height, h

• Case 2 - project an object straight up from the ground until it reaches peak

• Case 3 - project an object up a frictionless ramp (until it peaks)

4. introduced universal gravitational force law: Fg = (GMm) / r^2

5. showed that GMe/re^2 was equivalent to g or 9.8 m/s^2

6. derived Ug(r) = - GMm/r (see this video )

7. introduced the equation of greatness ...

8. discussed how the force is the negative derivative of dU/dx or dU/dr ... this is derived from the equation of greatness

9. discussed the general implications of knowing that the force is the negative derivative of dU/dx or dU/dr with a generic U(r) vs. r graph

10. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. reviewed the equation of greatness ...

4. reviewed how the force is the negative derivative of dU/dx or dU/dr ... this is derived from the equation of greatness

5. finished the general implications of knowing that the force is the negative derivative of dU/dx or dU/dr with a generic U(r) vs. r graph

6. discussed a problem with U(x) given...we found out a bunch of things once we knew the total energy and the velocity at a certain position

7. students worked M11 in class...we went over solutions.

8. discussed a new problem where F(x) was given. We had to use the equation of greatness to realize that we needed to calculate the work done by this variable force in order to determine the change in kinetic energy...in order to determine the final speed (initial velocity was given at a certain position)

9. discussed a problem in which U(r) was given. We had to use the equation of greatness to figure out the force.

10. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. viewed an MIT video about work, conservation of energy, potential energy

4. discussed how to interpret an Energy vs. x graph in general

5. students were challenged to revisit the Atwood's machine and find the final speed of the masses using

a. forces and the CA model

b. energy conservation

c. the blob method

6. students were challenged to revisit the physics of a mass sliding down a frictionless ramp and find the final velocity at the bottom using

a. forces

b. energy conservation

7. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. discussed what to do when you don't know what to do on hard problems

4. discussed a couple of MIT seat problems

a. mass fired by spring into loop de loop

b. bead sliding on ring being acted upon by gravity, ring normal force, and a spring

5. introduced the concept of power (definition and alternative ways of calculating power)

6. reviewed the calculus involved in power and showed how it is similar to the calculus of other physics concepts we have discussed to date

7. discussed several examples of average power and instantaneous power calculations

8. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. finished discussing last example of average power and instantaneous power calculations

4. discussed multiple examples in which energy/work was discussed while friction was present

5. students began working Mooney EOC MC and FR questions

6. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. discussed solutions to Mooney EOC MC and FR questions

4. Today's Recording - No Recording today

1. livestream

2. Unit 4 Energy Notes

3. discussed solutions to Princeton Review EOC MC and FR questions

4. discussed Unit 3 Exam MC Solutions

5. Today's Recording

1. livestream

2. Unit 4 Energy Notes

3. finished discussing Unit 3 Exam MC Solutions

4. students took Unit 4 Exam

5. Today's Recording