This is a problem I came up with myself, so it's not homework and so I didn't post in that forum.(adsbygoogle = window.adsbygoogle || []).push({});

Suppose a mass m1 rests on a frictionless table. m1 is directly connected to a massless ideal spring at equilibrium length of spring constant k which is connected to a string going over a pulley of mass m3 and radius r (and rot. inertia 0.5m3r^2), which is connected after the pulley to a mass m2.

Determine the equation for the motion of mass m1 when m2 is released. (dig. attached).

How would you go about doing this problem? I can't seem to get started because I can't figure out how to find the length the spring will initially be extended.

relevant equations:

F = -kx

Conservation of energy, probably.

All the angular/linear kinematics equations.

edit:sorry reread the rules just then, mods please move this to the homework forum (i thought the restriction didn't apply to independent study)

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# Spring attached to string on one side, mass on the other.

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