# 141 Winter 2018 Week 2

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Monday

Happy Martin Luther King Day! Have a dream of all people getting along!

Tuesday

Before Class
What if you want to see a video the second time and also want to see the questions? Just click on the small vertical bars at the bottom of the video that indicate where the questions are located in the video.

1. View Pushing Box Problem.
2. View this 3 minute video : Energy, Work, and Power. Be prepared to answer this question: a 1000 kg car starts from rest and accelerates to 30 m/s in 5 seconds. Please calculate the average power the car produces to do this. Please put answer in Watts and Horsepower.
• 2.0 Forces and Work
• 2.1 Power
• 2.2 Units
4. See this video of kids playing with rockets. It should help prepare you for how we’re going to do our project.
5. Big Exam! #1 solutions posted on main class website.

During Class
Prepare for your activity next Tuesday: You will make a video and calculate the kinematics, energy, momentum, power to be handed in next Thursday.

After Class

Wednesday

We are going to graph some of our own motion, forces, energy, and power tomorrow. I show you how I did it in #3 below. #2 is a super cool way to do it (in my opinion), but some students had difficulty getting the software to work. The full description of the project can be found on a link from the main class website.

Before Class. Please watch the following videos:

1. Please view the video kinematic graphs, LIVE! and watch me draw graphs on a board to represent my motion on a bicycle.
2. View Smarter Every Day Grasshoppers, and try to repeat his experiment with the other grasshopper. You may have an easy time doing this, or you may have great difficulty because of trouble with tracker software (I never got it to work myself). A past student wrote this to help tracker instructions. Please work together. In the face of fighting with malicious software, you need good friends. All the same, if it doesn’t work for you, please do your best to estimate the acceleration using my Excel method in the graphing video I did below. One student was able to get tracker to work on a Mac only after transforming the video into a .mov… here it is Grasshopper .mov
3. I graphed my motion without Tracker. Please view: Graphing running
4. See a video about one way to measure power.
5. Tomorrow, Thursday, we’re going to meet at Via Carta to take videos of us to calculate kinematics, forces, energy, power, and look at momentum conservation. The first project description link is on the main class webpage. Please take a look at it. I’ve never done this in the dark. It might be easier that way if you bring a light to put on you to follow.
6. Readings 2.3 Graphical Analysis of Kinematics
7. Find a description to project #1 on the main class website.

During Class
Warm up problems,
Practice and prepare for activity tomorrow.

Thursday: Meet at Via Carta Today!
we will take data about our movement and then we will analyze it in room 180-272 (NOT in our classroom), because this classroom has access to computers with Lab View on them.

Before Class.

1. Graphing a ball toss.
2. Please see how I solved the
3. Please see how we can collect our kinematic data using Logger Pro.
4. Please see how we can analyze our kinematic information from Logger Pro using Excel.