Reading: Chapter 8.
Exercises: 8.12  8.18 from the course text.
Homework 6, due March 3, 1010

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Homework 6, due March 3, 1010
Bill Goodwine, 376 Fitzpatrick
Re: Homework 6, due March 3, 1010
For the last part of Problem 8.17, to find the transfer function from the input voltage to the angular velocity, can we simply multiply the the transfer function from voltage to angle by s? Since the angular velocity is just the first derivative of the angle, then the Laplace transform of that would be s*theta(s) wouldn't it?

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Re: Homework 6, due March 3, 1010
Exactly.AL089 wrote:For the last part of Problem 8.17, to find the transfer function from the input voltage to the angular velocity, can we simply multiply the the transfer function from voltage to angle by s? Since the angular velocity is just the first derivative of the angle, then the Laplace transform of that would be s*theta(s) wouldn't it?
Bill Goodwine, 376 Fitzpatrick
Re: Homework 6, due March 3, 1010
Regarding finding the transfer function from the input to the output:
In class, we first took the Laplace transform of all the system equations, and then algebraically solved for the transfer function.
If it is possible to algebraically eliminate some variables before taking the Laplace transform (for example, for variables with no derivatives present), is that ok?
Thank you
In class, we first took the Laplace transform of all the system equations, and then algebraically solved for the transfer function.
If it is possible to algebraically eliminate some variables before taking the Laplace transform (for example, for variables with no derivatives present), is that ok?
Thank you

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Re: Homework 6, due March 3, 1010
Sure, it's exactly the same as eliminating them afterward. You can only algebraically eliminate variables before taking the Laplace transform if they always appear the same way, e.g., first derivative, of they only appear a few times so that you can differentiate one or more of the equations to get the term to appear the same way each time.mkiener wrote:Regarding finding the transfer function from the input to the output:
In class, we first took the Laplace transform of all the system equations, and then algebraically solved for the transfer function.
If it is possible to algebraically eliminate some variables before taking the Laplace transform (for example, for variables with no derivatives present), is that ok?
Bill Goodwine, 376 Fitzpatrick
Re: Homework 6, due March 3, 1010
Professor,
For Problem 8.13 it says
f = t for t<t<1, cos(t1) for 1<t.
Is this correct, or should it be
f = t for 0<t<1, cos(t1) for 1<t
For Problem 8.13 it says
f = t for t<t<1, cos(t1) for 1<t.
Is this correct, or should it be
f = t for 0<t<1, cos(t1) for 1<t

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Re: Homework 6, due March 3, 1010
You are right, it should beJosh wrote:Professor,
For Problem 8.13 it says
f = t for t<t<1, cos(t1) for 1<t.
Is this correct, or should it be
f = t for 0<t<1, cos(t1) for 1<t
t for 0<t<1
cos(t1) for t>1
Bill Goodwine, 376 Fitzpatrick