The door is made from one piece whose ends move along the horizontal and vertical tracks. If the door is in the open position. If the door is in the open position i.e. theta = 0 , and then released, determine the speed at which its end A strikes the stop at C . Assume the door is a 180 lb thin plate having width of 10 ft. a = 3.5 ft, b = 5 ft having a width of 10 .