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How do you work out Elastic strain energy in AS Physics? Watch

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    Can someone tell me how to work out elastic strain energy for Physics AS?? Please someone explain for me its doing my head in..

    Thanks in advance
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    Basically its Work done= Force x Distance moved

    so you use the equasion DeltaW=FDeltaL (Delts being that triangle.. change in)
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    (Original post by Keiran:.)
    Basically its Work done= Force x Distance moved

    so you use the equasion DeltaW=FDeltaL (Delts being that triangle.. change in)
    ok thanks, so what do u use the equation half ke squared for?
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      (Original post by mujahid_e3)
      ok thanks, so what do u use the equation half ke squared for?
      When you stretch a spring a distance x, the tension goes from 0 to kx, where k is the spring constant.
      Work done is force times distance, but the force was not constant.
      So we use the average force while the spring was being stretched.
      It went from 0 to kx so the average force was ½kx
      Multiply by the distance and you get ½kx times x
      ½kx²
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      (Original post by Stonebridge)
      When you stretch a spring a distance x, the tension goes from 0 to kx, where k is the spring constant.
      Work done is force times distance, but the force was not constant.
      So we use the average force while the spring was being stretched.
      It went from 0 to kx so the average force was ½kx
      Multiply by the distance and you get ½kx times x
      Thanks so in whcih cases do i use each formula?? When do i use ½kx² and when do i use ½ke??

      thanks!
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        (Original post by mujahid_e3)
        Thanks so in whcih cases do i use each formula?? When do i use ½kx² and when do i use ½ke??

        thanks!
        x and e can both usually stand for extension in the equations.
        The equation with extension in it is ½kx² or ½ke² for strain energy.

        I don't recognise the formula ½ke. Where has it come from?
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        I suspect that the other expression is supposed to be ½Fx - that is, half of the tensile/compressive force times the extension/compression. So, the choice is between ½Fx and ½kx². As for which one to use - it depends what you know in the particular question you are set. It should be clear from context.
       
       
       
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