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Impact speed

  1. Apr 9, 2009 #1
    How can I calculate the impact speed(final velocity) of an object of mass 100kg, dropped from a height of 100m, only considering gravity.
  2. jcsd
  3. Apr 9, 2009 #2


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    Pretty straight forward isn't it? Since you are only considering gravity, total energy is conserved. At height h, the object's potential energy, relative to the ground at height 0, is mgh. Since it is dropped, its velocity and so kinetic energy is 0. At the ground, height 0, its potential energy, relative to height 0, is 0 so all of that potential energy is converted to kinetic energy. Set the formula for kinetic energy equal to mgh and solve for v.
  4. Apr 10, 2009 #3
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