(adsbygoogle = window.adsbygoogle || []).push({}); Hi, I have no idea how to do this problem, wondering if anyone can help:

Two identical spheres, each of mass M and negligible radius, are fastened to opposite ends of a rod of negligible mass and length 2l. This system is initially at rest with the rod horizontal and is free to rotate about a frictionless, horizontal axis through the center of the rod and perpendicular to the plane of the page. A bug of mass 3M, lands gently on the sphere on the left. Assume that the size od the bug is small compared to the length of the rod. Express your answers to all parts of the question in terms of M, l, and physical constants.

a.) Determine the torque about the axis immediately after the bug lands on the sphere.

b.) Determine the angular acceleration of the rod-spheres-bug system immediately after the bugs lands.

Then later on in the problem, it states: The rod-sphere-bug system swings about the axis. At the instant that the rod is verticle determine each of the following:

c.) The angular speed of the bug.

d.) The angular momentum of the system

e.) The MAGNITUDE and DIRECTION of the force that must be exerted on the bug by the wphere to keep the bug from being thrown off the sphere.

So, I know that Torque = r * F or Torque = I * omega for part "a", but passed that I don't know where to go because I don't know what the force "F" would be and I'm not given the moment of inertia or angular velocity...

I'm really confused...

Thanks in advance for the help!

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# Homework Help: Angluar Momentum and Torque

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