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Force Needed

  1. Oct 13, 2007 #1
    i have a 230lb weight i need to lift 12feet in the air. i have a 2 1/8 inch dia. pulley directly above it, and then 17 feet horizonally i have a 3 inch dia. sheave block. Than i drop straight down 25 feet to another 3 inch dia. sheave block which is turned at a 30 degree angle to the sheave block above, but is still in line with the sheave block above. i then go down at a 110 degree angle for 8 inches to a 3 inch sheave block on a swivel hook, so i can line up with another 2 1/8 inch dia. pulley and onto a winch. what must my winch be able to pull to lift this 230 lbs. i am using a 1/8 inch steel cable rated at 1800 lbs break. Thanks ; Warrior Chief
  2. jcsd
  3. Oct 14, 2007 #2
    There is a fundamental principle that all a theoretical rope/wire/string can do is pull in a direction colinear with the rope/string/wire.

    So draw a diagram. Start at the weight and label the force the cable must supply. Then follow the cable, being careful what happens to the cable at each sheave. Come back and show your work.
  4. Oct 14, 2007 #3


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    Post a diagram of your setup...it sounds a bit confusing.
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