Elastic collisions 弹性碰撞If the internalenergy of the objectsdoes not change:- No change in temperature- No change in shape- No springs compressed- No new rotations or vibrationsKf = K;Then:
Elastic collisions 弹性碰撞 If the internal energy of the objects does not change: - No change in temperature - No change in shape - No springs compressed - No new rotations or vibrations Then: 𝐾𝑓 = 𝐾𝑖
Elastic collision of equal massesP1xiAt restP2xfAt restAfter thecollision:10P2f = Pii
Elastic collision of equal masses 𝑝2𝑓 = 𝑝1𝑖
Inelastic collisions 非弹单性碰撞If the internal energy of the objectsdoes change:- Change in temperature- Change in shape- Springs compressed, or- New rotations or vibrationsKThen:
Inelastic collisions 非弹性碰撞 If the internal energy of the objects does change: - Change in temperature - Change in shape - Springs compressed, or - New rotations or vibrations Then: 𝐾𝑓 ≠ 𝐾𝑖
Maximally inelastic collision("sticking collision") of equal massesP1xiAt restP1xfP2xfAfterthecollision:PiiP1f =P2f2
Maximally inelastic collision (“sticking collision”) of equal masses 𝑝1𝑓 = 𝑝2𝑓 = 𝑝1𝑖 2
How much kinetic energy was lost?P1xiAtrestP1xfP2xfAfterthecollision:Kii2Half of the kinetic energywas converted into heat
How much kinetic energy was lost? 𝐾1𝑓 + 𝐾2𝑓 = 𝐾1𝑖 2 Half of the kinetic energy was converted into heat