Lever is obtained as which is the mechanical advantage of the lever. This equation shows that if the distance "a" from the fulcrum to the point "A" where the input force is applied is greater than the distance "b" from fulcrum to the point "B" where the output force is applied, then the lever amplifies the input force. If the opposite is true that the distance from the fulcrum to the input point "A" is less than from the fulcrum to the output point "B", then the lever reduces the magnitude of the input force. Lever A lever ( or )
Lever frame Lever frame Mechanical railway signalling installations rely on lever frames for their operation to interlock the signals, track locks and points to allow the safe operation of trains in the area the signals control. Usually located in the signal box, the levers are operated either by the signalman or the pointsman. The world's largest lever frame (191 levers) is thought to have been in the Spencer Street No.1 signal box in Melbourne, Australia, which was decommissioned in 2008. The largest operational lever frame, meanwhile, is located at Severn Bridge Junction in Shrewsbury, England, and it contains 180 levers, although most