A catapult for throwing a missile or a stone to a long distance, consists of a support (fulcrum) at the center. The load (stone) is at one end of the bar or log. Then the effort to hold the load in balance is at the other end of the bar or log.
The arm distance between the fulcrum and the efforting force is adjusted so that the stone is sent to farther distance than otherwise.
Since fulcrum is in the center of load and effort , it is class 1 lever.
