The 60-ft telephone pole of essentially uniform diameter is being hoisted into the vertical position by two cables attached at B as shown. The end O rests on a fixed support and cannot slip. When the pole is nearly vertical, the fitting at B suddenly breaks, releasing both cables. When the angle θ reaches 10°, the speed of the upper end A of the pole is 4.5 ft/sec. From this point, calculate the time t which the workman would have to get out of the way before the pole hits the ground. With what speed v_A does end A hit the ground?

Transcribed Image Text:

A 60'B --y