Calculating the moment of inertia for this configuration

[Demon117]

Homework Statement

I need to find the rotational kinetic energy of this system in the figure I have provided. Here the spring is rotating with the system at angular speed \omega. The two beads on the wire move vertically, and the third bead is held by two massless rods of equal length L.

The Attempt at a Solution

Would the moment of inertia for the the whole thing just be

I_{1,3}=2mL^{2}

I_{2,3}=2mL^{2}

I_{total}=4mL^{2}

Any suggestions would be helpful.

 

[SammyS]

Homework Statement

I need to find the rotational kinetic energy of this system in the figure I have provided. Here the spring is rotating with the system at angular speed \omega. The two beads on the wire move vertically, and the third bead is held by two massless rods of equal length L.

The Attempt at a Solution

Would the moment of inertia for the the whole thing just be

I_{1,3}=2mL^{2}

I_{2,3}=2mL^{2}

I_{total}=4mL^{2}

Any suggestions would be helpful.

It looks as though the system is constrained to rotate about the z-axis.

You need to find the moment of inertia about the z-axis.

 

[Demon117]

Will it depend on the angle \alpha?

 

[SammyS]

Will it depend on the angle \alpha?

Yes it will depend on α .