problem-solving-with-oblique-collisions

Energy in 2D collisions

How do I find the kinetic energy loss from a collision?

• A common question, usually as a follow up to a collisions question, is to find the kinetic energy lost as a result of the impact

• If  kinetic energy is conserved in the collision

  • If  there will be a decrease in the total kinetic energy of the two particles

• Recall that kinetic energy can be calculated using 

• As the velocity is squared, its sign does not affect the kinetic energy

  • Hence, here is effectively the speed squared

• When dealing with motion in two dimensions, the velocity may be described in two components, e.g. 

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