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New here, inquiring mind seeking answers.

  1. Nov 4, 2012 #1
    Hello, this is my first post! I came here with a question- and I bet I will continue to have more. I hope this is a good place to seek answers. I am not a physics major / actually we didn't even have physics classes.

    But... I did an experiment the other day after watching a video about magnets and ball bearings () - well I thought what if the ball bearings where replaced by "multiple springs". Would this still work? I got a dowel rod and placed it vertically - then I put 4 springs together with a nut on each end and I recorded one long string vs several strings together...

    So here is my question : can placing multiple springs together be used to launch things in an exponential way? Has this been done before?

    That is my first question here- is this a good place to ask such questions? Thanks for reading!

    Last edited by a moderator: Sep 25, 2014
  2. jcsd
  3. Nov 4, 2012 #2


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    I think springs would absorb too much of the force. Ball bearings are very rigid and quickly transmit the force of the impact without losing much of it. Also, are you planning on using a magnet with these springs? That's why the trick in the video works. The ball bearing rolls down, is pulled towards the magnet at very high speed, and the force of the impact is transmitted to the last ball bearing with launches it outwards.
  4. Nov 4, 2012 #3
    Thanks for the reply Drakkith,

    I wasn't really planning on using magnets-
    I was planning on having a tall vertical rod with 4 (separate) springs at the bottom lined up one after the other vertically - with a bolt resting on the top of the 4 springs. (instead of having one long spring the same length as the 4). I will pull down the bolt towards the bottom, and release--- each spring will exponentially affect the next and push the bolt up a lot faster than one spring since they are separate --- wouldn't it? Would this work or do I need a physics lesson? :)
  5. Nov 13, 2012 #4
    Well, I decided to draw it, hope this works! I guess I am looking for the answer to this? Is it worth seeking?

    Attached Files:

  6. Nov 13, 2012 #5


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    There is no real difference between the two. Each single spring added together functions as one larger one. If you pull the block halfway down, the springs will be 50% compressed, just like the 1 large spring will be 50% compressed also.
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