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Solenoid as shock absorbers?

  1. Oct 25, 2011 #1


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    Is it possible to use a solenoid as a shock absorber?

    i.e run current through the solenoid, producing a magnetic field opposing a separate magnet attached to whatever it is receiving the shock impulse, thus dampening the effect according to the amount of current input.
  2. jcsd
  3. Oct 25, 2011 #2
    Edit* Nvm, I didn't see that you were wanting to run a current through the solenoid. This would be possible if you were able to link the current direction with the period of oscillations.
    Last edited: Oct 25, 2011
  4. Oct 25, 2011 #3


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    You do not need the seperate magnet.
    Attach whatever is receiving the shock impulse directly to the solenoid core, to provide a cushioning effect like a spring.
    A damper is still needed to reduce the amplitude of the oscillations.
    Last edited: Oct 25, 2011
  5. Oct 25, 2011 #4
    basically, if you have a solenoid with a ferromagnetic core, the core will tend to stay centered in the solenoid...then you can add a concentric shaft or rod (will need to be of a smaller diameter so the preference is still given to the core) and attache that to whatever you want to provide with shock absorption...
  6. Oct 25, 2011 #5


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    I don't understand why a change in current direction is necessary. If I run a current so that the effective N pole of the solenoid points in the +z direction and place a magnet above it with the N pole pointing in the -z direction, a switch in current direction would switch the direction of the solenoids magnetic field and thus attract the magnet above it, not providing the repulsion effect desired for the dampening of the shock impulse.

    Maybe I am interpreting this wrong but I don't see how this would work. By attaching the object receiving the shock impulse directly to the solenoid, the only cushioning effect provided would be from the coil of wires acting, literally, as a spring, not from any emf which is really what I'm going for. If I had a magnet, however, levitating above the solenoid, the opposing magnetic fields would provide a cushion of air, the magnet would oscillate up and down depending on external forces. Correct?
  7. Oct 25, 2011 #6
    You do not attach the whatever to the solenoid, but to the core in the middle of it.

    Does your solenoid attracts iron?
    Have you try to put a pvc pipe inside your solenoid and piece of iron inside the pvc pipe?
    What does it do? does it fall? does it stay?
    ...hope you are starting the get the picture now...also, refer to my previous post.
  8. Oct 26, 2011 #7
    Last edited by a moderator: Apr 26, 2017
  9. Oct 26, 2011 #8
    Do you mean the application of Lenz's Law?
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