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**inelastic collision....kinetic energy lost?**

**1. Homework Statement**

a bullet with a mass of 6 g is fired through a 1.25kg block of wood on a frictionless surface. initial speed of the bullet is 896 m/s and speed of bullet after it passes through it is 435 m/s. whats the final velocity? how much KE is lost?

**2. Homework Equations**

ke lost=ke initial-ke final

ke lost=1/2mvf-1/2mvi

i got 11.2 m/s for the final velocity of the wood

**3. The Attempt at a Solution**

KEi=1/2(.006)(896^2) + 0

KEf=1/2(.006)(435^2) + 1/2(1.25)(11.225^2)

i got 2408.228 - 488.925

thats not negative..where did i go wrong??

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