Explanation

According to the positions of effort, fulcrum, and load, levers are divided into three kinds:

1. First kind of lever: The fulcrum is located between the effort and the load. Examples: See-saws, crowbars, hammer claws, scissors, pliers and boat oars.
2. Second kind of lever: The load is located between the effort and the fulcrum. Examples: Bottle opener, wheelbarrow, nut cracker, nail clippers, nail cutter, paper cutter and door.
3. Third kind of lever: The effort is located between the fulcrum and the load. Examples: Broom, tongs, human arm, stapler, fishing rod and tweezers.