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Pondering over this thought experiment, a question comes to mind -- to which my brain sometimes replies "of course" and sometimes "no way!"A disk shaped satellite ("in zero-G") spins about its axis. There are two thrusters mounted as shown on two axial booms. The thrusters are fired briefly at some moment. We want to try and predict the effect of the thrusters while looking at the system as a co-revolving observer (e.g. we're strapped into a seat on a huge ring or shell that surrounds the disk symmetrically, and is initially rotating at the same angular velocity).
In other words, we want to predict the behavior of the disk, with respect to a rotating reference frame that the disk was stationary in before the thrusters were fired -- and this frame is not affected by the thrusters.
The question is, do we need to consider the disk to be a gyroscope -- and hence, do we need to grapple with some complicated precession stuff?
OR... can we ignore the rotation and just consider the disk as a simple moment of inertia that is acted upon by a torque?
In other words, we want to predict the behavior of the disk, with respect to a rotating reference frame that the disk was stationary in before the thrusters were fired -- and this frame is not affected by the thrusters.
The question is, do we need to consider the disk to be a gyroscope -- and hence, do we need to grapple with some complicated precession stuff?
OR... can we ignore the rotation and just consider the disk as a simple moment of inertia that is acted upon by a torque?
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