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Conservation of momentum and % of energy loss

  1. Sep 18, 2015 #1
    Suppose a block of 10kg at 10m/s collides into a block of 5kg at 0m/s.

    Does a given percent of energy loss in the collision affect the final velocity of the blocks after the collision?

    For instance, if there is no energy lost in the collision, would the final velocities be faster than if there is 10% energy loss in the collision? If so, then, how is momentum conserved if energy loss can change the final velocities?

    Thank you
     
  2. jcsd
  3. Sep 19, 2015 #2

    jtbell

    User Avatar

    Staff: Mentor

    Yes.
    Momentum is a vector (direction matters), but energy is a scalar (direction does not matter). Consider two objects with equal masses and speeds, moving in opposite directions. The total energy depends on the speed. The total momentum is zero, regardless of the speed.
     
  4. Sep 21, 2015 #3
    Thank you jtbell
     
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