Posted by peter on .
I don't know where to begin with this question. Could someone help me please?
A rod of mass 4.1 kg and length 1.6 m hangs from a hinge as shown in the figure below. The end of the rod is then given a "kick" so that it is moving at a speed of 5 m/s. How high will the rod swing? Express your answer in terms of the angle the rod makes with the vertical.
college physics -
The angular momentum of the rod right after the kick is given by
I*w = (1/3)M*L^2*w
where w = ( 5 m/s)/L = 3.13 rad/s
I*w = 10.95 kg*m^2/s
Next, compute the total kinetic energy at the start of the upward swing.
KE(max) = (1/2)*(I*w)*w
That equals the increase in potential energy at maximum deflection angle A. That angle is determined by the center of mass location.
Check my thinking. I am leaving the rest up to you.