Using Elastic Potential Energy in Energy Conservation Problems

Today we basically did several examples of energy problems that include springs:

Notes: Elastic Potential Energy and Energy Conservation

At the end of the period I asked you to finish Energy TIPERs #6, then we checked it together and you kept it. Please do not turn that in.

Suggested HW: p.160 #35, 39, 67. Tomorrow will be a work day. You might have picked up the Energy Test Practice in class today, too.

Here is the solution to the last problem in the notes:

Elastic Potential Energy

After doing a Plickers, we defined elastic potential energy.

Notes: Elastic Potential Energy

Suggested HW: front of Energy TIPERs #6 - we'll do the back tomorrow.

Lab: Efficiency of a Ramp

Today you completed a small lab to find if the angle of an inclined plane affects its efficiency as a machine:

This lab is short enough that most of you finished AND got yours checked in class. I also checked your labs from last Wednesday while you were working.

You have some suggested homework, with a Plickers on Wednesday: p.162 #47 & 89

Machines and Efficiency

First, I forgot my phone today, so the Plickers problem we were going to do from last night's suggested homework has been pushed to next class. This means there may be more than one Plickers problem next class.

Today we very briefly talked about machines and efficiency.

Notes: Machines

Your suggested homework is a little half sheet called HW: Machines.

On Monday/Tuesday nest week you will be completing a lab. The goal is to answer the question: does the angle of a ramp affect its efficiency? If so, what is the relationship? How you answer this question is up to you, so think about it over the weekend.

Power

Notes: Power!

Suggested homework: p. 162 #45, 50 (use Watts instead of horsepower), 56

Lab: Energy of a Bouncing Ball

Today you had all day to work on a little lab:

If you didn't finish it in class, finish for homework tonight. When it's done, show it to me in your notebook. We are doing another lab on Mon/Tues - I will definitely be asking to see this one while you're working on that one.

Work Due to a Variable Force + Work Problems Practice

Today we found the work due to a variable force with graphs and used that to find velocity at a given position.

Notes: Work Due to a Variable Force (remember to download and run as a slideshow)

We practiced in class with Energy TIPERs #4 (email miss.volkening@gmail.com for a copy). We went over the answers in class.

Suggested homework for this content is p. 163 #59, 60, 61.

Then we did a problem together (see below) and started working on Energy TIPERs #5. You might not have finished in class. Although Energy TIPERs 5 is suggested only and you will not be turning it in, please try to finish it sometime and check your answers in the answer key binder. The back especially is a really good problem - it is actually from an old AP test.

Here is the problem we did solved without numbers:

Work

What is work? This is not a philosophical question.

Notes: Work

We worked on Energy TIPERs #3 in class today, which you kept as notes.

Suggested homework is p. 158 #8, 9, 13, 16. If you never completed p.160 #25, 33, 37, you might want to try those too.

Energy Conservation Practice

I'm still pretty wiped out from the PSAT yesterday, and you must be too, so today is a work day. You are working on:

1. Energy TIPERs #1 and #2, which we will go over at some point in the class.

2. Energy Conservation Practice. This is new today, up front on the counter. I will have a Plickers off of it tomorrow.

3. p.160 #25, 33, 37. I don't know when I'll hold you responsible for this suggested problems set, but please work on it eventually. Maybe this weekend?

We'll have new content tomorrow.

Mechanical Energy

Today we started talking about mechanical energy and its conservation:

Notes (remember to run as a slide show!)

This left about 10-15 minutes left in the period, but hopefully you used it to start your suggested homework:

• Energy TIPERs #1 (email miss.volkening@gmail.com or reply on Remind for a copy)
• Energy TIPERs #2 (email miss.volkening@gmail.com or reply on Remind for a copy)
• p.160 Problems #25, 33, #37.

NONE of these are due on Wednesday - you have the PSAT on Wednesday.  On Thursday, we'll go over some of these together and/or use Plickers, and have some work time to review similar problems.