Fall 2016 Mechanics Week 6

This week, we will examine an object that circulates into a circular path… like how the moon doesn’t travel in a straight line because the attractive force of gravity between the earth pulls the moon into a circular path.

For Tuesday,

First Hour, we look at centripetal acceleration. PS#5 Posted! Please take a look!

Before Class

• Please read an important document sent to me by the department chair, Bob Echols.
• SO! when you watch videos, do you answer the questions to get them done and move on, or do you actually read the comments for a wrong or right answer? I find this information very important and put it there because it confronts common misunderstandings and/or mistakes students make. Please give it a try and let me know what you think.
• I posted some of your solutions for MT#1 on the main website. Because there are many different ways to solve most problems, I provided two good solutions for each question. Please make use of them as you see fit.
• Thanks for sharing your thoughts with me Thursday. I’ve posted your feedback on the main class website and actually have many questions and thoughts to share myself (in purple on the document). Please read it and see if it provides insight about where I am with the class as well as where your colleagues are with all this. Thanks
• Watch derivation of Centripetal Acceleration and how to use it. Make sure you can do this for Big Exam.
• If we look at the earth spinning in space, we might notice that there’s nothing making it turn… that it is free of external torques. We might consider that we’d then look at the earth through the lens of angular momentum. What could we learn? Please see video on Coriolis Effect made by students from Fall, 2014. Look for a number of things:
• Do we understand the Coriolis Effect?
• Do we see the value in looking through the angular momentum lens?
• Are we getting ideas for how we’d like to make our final video project?

Second Hour we look at universal gravity and the inverse square law.

For Thursday
First Hour
circular dynamics with more than one force. It’s just like the elevator problem, but the acceleration is centripetal acceleration.
Before Class

• Please read through PS#5 (posted on main class website) spending at least 10 minutes on each one. Please come to class with questions. Make sure you evaluate things from lens and make a good detailed drawing. You’ll want to watch the videos before trying some of them.
• Solutions for Big Exam #3 and PS #4 posted on Class website.
• You guys pointed out to me that 5.1 Universal Gravitation was not accessible. Some of you found the correct chapter (13.1) in the OpenStax University Physics book… good job. Anyway, I’ve fixed the link (above), so please try again to read 5.1 if you haven’t already.