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Force need to break a magnetic lock

  1. Apr 9, 2013 #1
    Force need to break a magnetic lock NOT SOLVED

    So rest assured I'm not planning a prison break. I work in a secure treatment center for adolescents and the other night we had an escape. Many of the staff are amazed at the ease they busted the lock. I looked at it and there is a lot of play on the top and bottom. Having just completed half of a physics for scientist and engineers I thought I can figure how easy it is and maybe come up with better lock placement. So here is the raw data.

    I looked up and found a similar lock system they have on some of the other doors here it is.


    So it's 1200 lbs force but the gate but all doors and gates have one lock what is the formula or how do I calculate the ratio of movement required to break the lock.

    This gate the lock sits in the middle of a chain link fence that's about 9 feet high if I pushed the bottom have far or with what force is required to break the bond.

    I'm thinking a if only one lock has to be used placing the lock towards the ground more would leave it more secure given the higher up due to height limitations of humans would be better.

    Hey I'd love some help sucking up t.o my bosses so please help me learn what I need to figure this stuff out.

    Ps I got another question ill ask later about another work related question.
    Last edited: Apr 9, 2013
  2. jcsd
  3. Apr 9, 2013 #2

    Simon Bridge

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    There is a lot of play on the top and bottom of what?
    You mean if you push the top of a door or gate, the door will bend a lot around the lock?

    I don't see any "raw data".

    Though it take 1200lbs to force the lock open, under rated operating conditions, someone could apply more than that by using some sort of lever. It is also possible that the locks are not being used under rated conditions.
  4. Apr 9, 2013 #3
    Your right lacking the raw and I'm going to guesstimate and make a few broad assumptions. The lock lets say has a set holding force of 1200 lbs here is another lock with a higher force


    I'm unsure what is meant by holding force if it can be viewed like a static friction or not.

    The lock is like 8" by 2" and on the 9' gate roughly in the middle this gate is a chain link fence with the standard galvanized steel tubing so yes the further away from the lock the easier it is to move the outer portion of the gate which would inturn cause more pressure or stress on the lock plate due to the. Static position of the lock plate the motion would be in an arc. So if the length of the portion of the fence is 4.5' the radius of the arc would be that.

    I have no idea and just guessing I would imagine that I would be looking at the exact point of distance from initial position it takes to greater then or equal to the holding power. I wold think the equation would be something like the

    ΔS=Ar/μholding force

    But I don't know if this is how it would look or if this is totally wrong. Lets see if I provided enough info this time and Ty for getting me to provide more info
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