What are examples of first class levers?
• Seesaw (also known as a teeter-totter) • Trebuchet • Crowbar (curved end of it) • Hammer Claw, when pulling a nail with the hammer’s claw • Hand trucks are L-shaped but work on the same principle, with the axis as a fulcrum • Pliers (double lever) • Scissors (double lever) • Shoehorn (used for putting feet into shoes) • Spud bar (moving heavy objects) • Beam engine although here the aim is just to change the direction in which the applied force acts, since the fulcrum is normally in the center of the beam (i.e. D1 = D2) • Wheel and axle because the wheel’s motions follows the fulcrum, load arm, and effort arm principle. • Chopsticks with hand the middle finger acts as a pivot. The whole system is a double lever.
