Swing!
Based off requirements from January 2022.
This module is designed to help you explore how engineering and simple machines called levers affect your life each day. Engineering is considered the application of scientific and mathematical principles to create the design, manufacture, and operation of structures, machines, processes, and systems. Engineering is very closely aligned with technology.
- Wolf Cub Scouts: Paws of Skill
Paws of Skill: Levers are used in many sports, including baseball, golf, and tennis.
- Bear Cub Scouts: Baloo the Builder, A Bear Goes Fishing
Baloo the Builder: Using a lever (crowbars, pliers, screwdrivers, hammer, etc.)
A Bear Goes Fishing: Using a lever (a fishing rod)
- Webelos Scouts: Engineer
Engineer: Entire adventure deals with engineering.
Option A: With your parent’s or guardian’s permission, take an old or broken household or mechanical item, break it down into its component pieces, and identify the purpose of five parts. Suggested items include a keyboard, floppy disk, telephone, VCR, tape deck, bicycle, people counter, printer or similar item. Make sure to use appropriate safety precautions.
Option B: Participate in two sports, either as an individual or part of a team, and identify the levers used in each sport.
Show:
- How each lever works
- How the lever in your design will move something
- The class of each lever
- Why we use levers
A lever is a rigid bar that turns around a fulcrum, or fixed point. The force—a push or a pull that is applied to the lever—is called the effort. The farther the effort is from the fulcrum, the easier it is to use the lever. What the lever moves is called the load or the resistance. Levers can change the direction of motion, make it easier to move something, or cause something to move a greater distance. There are three classes, or types, of levers. Class 1 lever—The fulcrum is located between the effort and the load. The load always pushes down because of its weight. The force applied will push up on the load.
In a class 1 lever, you push down. Even though you are pushing down because of its weight, the load will be lifted up. Also in a class 1 lever, you apply force in the direction opposite the direction you want the object to move. Depending on where the fulcrum is placed, a class 1 lever can make the load either move more easily or move a greater distance. Examples of class 1 levers include seesaws, crowbars, scissors, and pliers.
Class 2 lever—The fulcrum is at one end, the effort is at the other end, and the load is in the middle. The effort and the load move in the same direction. In a class 2 lever, the load pushes down, but you lift up to lift up the load. A class 2 lever makes an object easier to move. Examples of class 2 levers include wheelbarrows, catapults, bottle openers, screwdrivers, nutcrackers, staplers, and wheelbarrows.
Class 3 lever—The fulcrum is at one end, and the effort is applied between the fulcrum and the load. In a class 3 lever, you push in the direction you want the load to move. A class 3 lever makes an object harder to move but moves the object a much greater distance than the effort moves, such as a hammer driving a nail. Because the load end moves faster than the effort (it has to travel farther during the same amount of time), the load gains speed, such as swinging a baseball bat or golf club. Many sporting activities use class 3 levers, such as baseball bats, tennis rackets, canoe paddles, golf clubs, and fishing poles. Other examples of class 3 levers include the human arm, brooms, shovels, tweezers, and staple removers.
Bats, clubs, rackets, paddles, and fishing poles are class 3 levers.
Levers can be used to:
- Make things easier to move—A small force applied over a large distance results in a large force moving a small distance (class 1 levers where the applied force is farther away from the fulcrum than the load, and class 2 levers).
- Change the direction of the applied force (class 1 levers).
- Increase the distance an object moves—A large force applied over a small distance moves the load a large distance. (This happens with class 3 levers and class 1 levers where the fulcrum is closer to the applied force than the load.)
- Playground—Seesaws (class 1), swings (class 2), and sandbox shovels (class 3)
- Carpentry shop—hammers (class 3; the hammer’s claw is a class 1)
- Construction site—crowbar (class 1, pliers (class 1), backhoe (class 1; see http://leo.koppel.ca/backhoe/levers.html), shovel (class 3)
- Restaurant kitchen—can opener (class 1), spoons and forks (class 3), bottle opener (class 2)
