Question

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B
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a thin uniform rod (mass 3.9 kg,
length 3.9 m) rotates freely about a horizontal axis A
that is perpendicular to the rod and passes through a
point at a distance d= 1.0 m from the end of the rod.
The kinetic energy of the rod as it passes through the
vertical position is 20 J. (a) What is the rotational
inertia of the rod about axis A? (b) What is the (linear)
speed of the end B of the rod as the rod passes
through the vertical position? (c) At what angle o will
the rod momentarily stop in its upward swing?