Make a Pulley:
- Empty spool of thread
- Pencils and pens
1) Grab several pens or pencils and tie them in a bunch with the string around the middle.2) Pull up on the string and lift the bunch.
3) Put a pencil or pen through a spool of thread and hold it up by the end. This would be easier if you had someone else hold the two ends of the pen/pencil for you.
5) Pull the loose end of the string down. Can you notice that the pencil bundle weighs less?
A simple pulley, like the one you made, should cut the weight in half.