Pulleys, Mechanics

Pulleys

In this exhibit I wanted to show that the mechanic advantage of pulleys.  I wanted the user to understand that the more pulleys used, the easier it is to pick something up and the lighter this object feels.

I set up 3 pulleys and had one heavy jar of sand.  The user would then try to pick up the jar of sand with the pulleys and notice how with more pulleys the jar would feel lighter and be easier to pick up.
I placed three pulleys side by side in order that the user could compare using them very easily. The sign is to inform the user on what to pay attention to.

Here are videos of the jar being picked up with different pulley systems.

The first video is using the one pulley system.

Here are the two other pulleys systems.

I had trouble figuring out how to properly make the interaction better for the string would get tangled and the pulleys would fall off the string.  However two of the exploratorium staff in the room came up with this jam mechanism that stopped the pulleys from falling off the string and kept the string untangled. 

I had trouble figuring out how to properly make the interaction better for the string would get tangled and the pulleys would fall off the string.  However two of the exploratorium staff in the room came up with this jam mechanism that stopped the pulleys from falling off the string and kept the string untangled.