Reading: You should have read everything from Chapter 1 through Chapter 4 by now. The first exam will cover this material.
Exercises: 4.3, 4.4, 4.7, 4.9, 4.10, 4.12, 4.14, 4.19 and 4.22.
Homework 5, due September 29, 2011.

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Homework 5, due September 29, 2011.
Bill Goodwine, 376 Fitzpatrick
Re: Homework 5, due September 29, 2011.
Can you give a suggestion on how to solve Problem 4.14? I do not know where to start.
Re: Homework 5, due September 29, 2011.
Also, I'm confused as to how to solve for the homogeneous solutions in Problem 4.22 because it involves x and y terms. How should we do this?

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Re: Homework 5, due September 29, 2011.
Write F=ma for the board. The forces on the board are at two points due to friction by each roller. If the board moves the normal force supported by each of the rollers changes.pat wrote:Can you give a suggestion on how to solve Problem 4.14? I do not know where to start.
I actually had this on the final exam one year.
Bill Goodwine, 376 Fitzpatrick

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Re: Homework 5, due September 29, 2011.
I emailed the whole class about this one.pat wrote:Also, I'm confused as to how to solve for the homogeneous solutions in Problem 4.22 because it involves x and y terms. How should we do this?
Bill Goodwine, 376 Fitzpatrick
Re: Homework 5, due September 29, 2011.
On 4.12 are we supposed to account for the gravitational force?
Re: Homework 5, due September 29, 2011.
What are you looking for when you say to get approximations to steadystate solutions for equations by looking at graphs like in 4.4 or 4.7? There's nothing remotely similar to that problem in the book or what we did in class. thanks.

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Re: Homework 5, due September 29, 2011.
The graphs present all the information you need for the steadystate solution. The "approximation" partly only means that you can only approximately read the values from the graphs. Just ask yourself what those graphs are showing.astumpf wrote:What are you looking for when you say to get approximations to steadystate solutions for equations by looking at graphs like in 4.4 or 4.7? There's nothing remotely similar to that problem in the book or what we did in class. thanks.
Bill Goodwine, 376 Fitzpatrick

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Re: Homework 5, due September 29, 2011.
Someone asked me:
Gravity and the forcing function are supposed to be separate.For homework question 4.9, it asks to find the equation for motion for figure 4.25. When doing this, do we take into account the forcing function and the gravity separately or do we assume that the forcing function in the figure is the force of gravity? Thanks!
Bill Goodwine, 376 Fitzpatrick