The uniform 37-lb bar with attached 14-lb wheels is released from rest when θ = 60°. If the wheels roll without slipping on the horizontal and vertical surfaces, determine the magnitude of the angular velocity of the bar when θ = 32°. Each wheel has a centroidal radius of gyration of 7.1 inches.

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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the answer would be   dignified - apex

this is poiselle's equation from fluid mechanic in physics. mech eng