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Is their a formula to measure the amount of force needed to break an object over time

  1. Nov 6, 2011 #1
    I was splitting some wood the other day with an old maul and the maul broke. I was wondering if anyone knows of a formula to predict or give a sum of the force needed over time to break said maul.

    so what i really wanna know is how many times can i hit something with 600lbs of pressure with a maul that breaks after 1200lbs of pressure or.. how many beers can i open with a force of .000001lbs with a bottlecap remove that breaks after 70lbs of pressure?
     
  2. jcsd
  3. Nov 6, 2011 #2
    Re: Is their a formula to measure the amount of force needed to break an object over

    Hahaha There were actually no theory for that problem.
    The only way to find out is to do it until it get broken.
     
  4. Nov 6, 2011 #3

    boneh3ad

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    Re: Is their a formula to measure the amount of force needed to break an object over

    There is plenty of theory actually, but no general equation for it. It depends so heavily on the nature of the force, how often it occurs, the shape and material of the object and many other things. Look up fatigue life. That would be a good place to start.
     
  5. Nov 9, 2011 #4
    Re: Is their a formula to measure the amount of force needed to break an object over

    kk, thanks guys... not a big deal just curious... i look into fatigue life
     
  6. Nov 9, 2011 #5
    Re: Is their a formula to measure the amount of force needed to break an object over

    Way too complex for almost all materiels... ordinary glass for instance will deform over a long time due to pressure or gravity (old glass bottles you find in dumps are folded flat, old stained glass windows get thin at the top and thick at the bottom). Then, if you fracture glass, the speed of advancement of the crack can exceed 5000 feet per second, yet even what appears to be the motionless end of a static crack is really still continuing to advance very slowly as the molecular bonds maintain a minimum breaking rate (on the order of hundreds of bonds per hour for typical pane glass)... and that's just "simple" glass.
     
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