# Homework Help: Dynamics of a spring contrained string over a pulley.

1. Jan 18, 2008

### MightyG

1. The problem statement, all variables and given/known data

http://img166.imageshack.us/img166/4254/tut5q3ue5.jpg [Broken]

2. Relevant equations

3. The attempt at a solution

iv had a go at this and I think im getting it right but just looking for a bit of clarification since my lecturer isnt giving out answers, helpfull....

ive started off by saying that initially the system is stationary and equilibrium so,

K.X_in = M.G
X_in = (M.G)/K

so MGR - K(X_in+X)R=I(alpha) sub in X_in = (M.G)/K

(MGR) - ((KMGR)/K) - (KXR) = I(alpha) simplify and sub in X=R(theta)

so,

K(R^2)(theta) + I(alpha) = 0

so (omega_N) = R SQRT(K/I)?

any help would be very very helpful!!
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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Last edited by a moderator: May 3, 2017
2. Jan 19, 2008

### Tom Mattson

Staff Emeritus
Your solution is a bit hard to read. Could you possibly type it up in LaTeX? Here is a tutorial for using LaTeX at PF:

Also, I don't see where you've used the $h$ anywhere. Are you using a different symbol for that?
@Tom Mattson for the frequency he does not need to consider $$h$$