Levers and pulleys are two basic simple machines. They make moving and lifting things easier, and are incorporated into many aspects of our everyday lives. These simple machines use mechanical force to multiply your normal strength, and can be customised to move specific amounts of weight with as little force as possible. Projects can be designed for kids to help them understand the basic concepts of simple machine and mechanics.
Send A Snack
For this experiment you will need two thread spools, 40 feet of string, two round pencils, paper clips and a small bag of chips. Tie the ends of the string together to make a large loop. Next, stick the pencils through the hole on each of the spools. Hold one pencil so the spool moves freely. Have another person stand in the opposite end of the room with the other spool, and carefully wrap the string around each spool. Attach the chips to the string using paper clips, and pull on the string to move the bag from one side of the room to the other.
Tie a length of rope into a loop. Hang this loop from the branch of a tree. Connect two pulleys to the loop of rope using S-hooks. Attach another pulley to the handle of a basket using an S-hook. Attach another rope to the handle of your basket before threading it through a tree pulley, then down through your basket pulley and up through your second tree pulley. Thread a 6-inch length of PVC piping over the end of the rope before tying it back to itself to form a handle.
Place a Popsicle stick on top of a pencil to make a simple lever. Place a large dried navy bean on one end, and drop a large coin onto the other. Pay attention to how high the bean jumps. Continue to experiment by dropping the coin from different heights, on different areas of the Popsicle stick and replacing the pencil with a thick marker for a wider fulcrum. Take note of how high the bean jumps, and which way is the most effective to launch it the highest.
See Saw Lever
Balance a 10-foot long 2 by 4-inch board on a strong chair and create a see-saw. Place different sized people on each end, and experiment with where to move the fulcrum to balance two people. Try again with another set of people, and note any differences you see.