can energy be destroyed?

[ninus maximus]

a 80 kg mass traveling at a velocity of 18 m/s

 

collides with

 

a 80kg mass traveling at a velocity of 18 m/s

 

KE=.5 (m1v)^2=12960 j

 

KE=.5(m2v)^2= 12960 j

 

non elastic collision and boom

 

energy destroyed.

 

the two masses merge but they dont have velocity so no kinetic energy.

[insane_alien]

the energy isn't destroyed, it is converted into non-kinetic forms of energy.

 

most likely heat, but could take other forms such as sound, light, or even chemical energy.

 

your conclusion that energy is destroyed comes from a dodgy analysis of the situation rather than any flaw of physics.

[swansont]

Two objects colliding inelastically will deform, and that takes energy as well.