Search and Rescue with rope and pulley

This device is called a BLOCK AND TACKLE

You can print out this page for you FOG manual.

I carry 2 small pulleys and a 200 foot rope in my CERTS back pack. Here is why:

Stringing a rope through one fixed pulley does not multiply the effort force required to move an object, it just changes the direction of pull. However adding a second moveable pulley does multiply the effort of force (using the fulcrum principle), creating a mechanical advantage greater than one. The mechanical advantage can be calculated by counting the number of support ropes excluding the pull rope. Connecting two or more pulleys together in this manner is called a "BLOCK AND TACKLE". Two pulleys shown in the illustration above as a Block and Tackle would double the amount of weight you could move compared to your using a single direct rope or just one pulley.

A normal Block and Tackle has 3 pulleys built into each "BLOCK", thus increasing the lifting power by 6 times.

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