How do levers work?
Levers are used all over the place in our everyday life. But have you ever wondered just exactly how they work? Grab your favorite budding scientist and tackle this fun project — and before you know it, you'll both be lever experts!
A lever works by reducing the amount of force needed to move an object or lift a load. A lever does this by increasing the distance through which the force acts. In this experiment, you will show that the closer the fulcrum — or the pivot point of the lever — is moved toward the load, the less effort is required to lift the load. At the same time, the distance over which you must apply the force increases. You will see that levers neither increase nor decrease the amount of total effort necessary. Instead, they make the work easier by spreading out the effort over a longer distance.
- 12-inch wooden craft board or ruler
- 2 clear plastic cups labeled LOAD and EFFORT
- 100 pennies
- 18 glass marbles, or a weight or large stone that will fit into the cup
- Large metal binder clip, with the silver arms removed
Prepare the arm
Glue the labeled LOAD and EFFORT cups to each end of your lever arm, as shown. If you are using a wooden craft board, you'll want to make inch marks along one side. They will help with the fulcrum placement. Put your marbles, weight or rock into the cup labeled LOAD.
Set up the lever
Tape your binder clip, flat side down, onto a stable, flat surface. Start by placing the lever arm onto the binder clip 4 inches from the end marked LOAD.
Start placing the pennies in the cup marked EFFORT one at a time and record how many pennies it takes to lift the EFFORT cup into the air. Move the fulcrum — or pivot point — away from the LOAD cup 1 inch at a time and add more pennies as necessary. Don't forget to record your results. You should notice that the farther away the fulcrum moves from the LOAD cup, the more pennies are required to lift the load.
- 4 x 6-inch photos of experiment, printed at a lab or home printer on photo paper
- Elmer's 16 x 20-inch foam board
- Elmer's Board Mate Extra Strength Glue Stick
- Cardstock in various colors
- Sticker letters and numbers (optional)
Plan your layout
Use a ruler and a piece of scrap paper and make a rough sketch of what you'd like the finished poster to look like. Keep in mind how big you'd like your title to be, how much room you have for your project explanation and where the pictures are going to go.
Create poster elements
Several options exist for creating the letters for the poster. The easiest method is to purchase letter stickers in various colors, shapes and sizes. To make your own custom lettering, create your words in a word processor program and print the words out directly onto the card stock. Make sure to edit your font to create just the outline of the letters, with a transparent fill. In Microsoft Word, this is easily done using Text Effects and choosing the transparent letter with a shadow. Once your letters are printed, carefully cut them out using a craft knife or scissors. When cutting out a cursive font, take care to ensure each word stays joined. That will make your assembly much easier.
Create the text
Type and print out the text for your poster on card stock, trim away excess paper and back it with card stock that's of a coordinating color and is an inch wider and taller.
Put it all together
Use the Elmer's Extra Strength Glue Stick to secure all of the elements to the board, taking care to glue down all corners to prevent them from curling up.
This post was sponsored by Elmer's.