The three classes of levers are —
(i) Class I levers — In this type of levers, the fulcrum F is in between the effort E and the load L.
Example — a seesaw, a pair of scissors
(ii) Class II levers — In these type of levers, the fulcrum F and the effort E are at the two ends of the lever and the load L is somewhere in between the effort E and the fulcrum F.
Example — a nutcracker, a bottle opener.
(iii) Class III levers — In these type of levers, the fulcrum F and the load L are at the two ends of the lever and the effort E is somewhere in between the fulcrum F and the load L.
Example — sugar tongs, foot treadle.
