How to Build a Pulley With Liter Bottles & Rope

Machines have provided ways for humans to breeze through just about all types of activities. One of the most famous models for simple machines is the pulley. Known for its inclined planes and levers, a pulley can help reduce your workload by carrying any object from one floor to another. By simply pulling on its ropes, you can transport objects to different places. You can make your own pulley using a few liter bottles and a rope. This will help you demonstrate to kids just how pulley systems work.

Things You'll Need

• Wire coat hanger
• Scissors
• Rope
• Wooden spool
• Liter bottle
• Cup hook
• Clothesline pulley
• Yardstick
• Book
• Masking tape
• Binder clip

Instructions

Fixed Pulley with Liter Bottles and Rope

1. Cut the center of your wire hanger’s straight, horizontal portion using your scissors. Insert and crisscross the hanger’s severed ends through the hole of the spool.

2. Adjust the hanger so that the spool can rotate easily. Bend the wire’s ends to prevent your spool from coming loose.

3. Place your hanger on a cup hook. Cut a piece of rope with enough length to start from the ground, loop around your pulley and drop back to the ground. See to it that there is additional rope for you to tie around the liter bottle.

4. Tie the rope around your liter bottle and loop the rope around your pulley. Pull on your rope to lift the bottles.

Movable Pulley with Liter Bottles and Rope

1. Tape the yardstick to your table. Allow 3 to 4 inches of the yardstick to hang off the edge.

2. Place a book on top of the ruler to hold it in place. Cut a long rope and clip one end of it to the ruler’s edge. The ruler must be hanging off the table with the binder clip.

3. Loop the rope right through the pulley so that it sits in the middle of your rope. Cut off a shorter piece of the rope using your scissors.

4. Tie an end of the pulley’s center bolt and tie the other end to your liter bottle.

5. Pull on the loose end of your long rope. This should lift up the bottle hanging from your pulley.

References

• Kendall Hunt : An Introduction to Pulleys
• Canada Science and Technology Museum: Make a Simple Pulley

Resources

• Read this Article in Spanish