# NTNUJAVA Virtual Physics LaboratoryEnjoy the fun of physics with simulations! Backup site http://enjoy.phy.ntnu.edu.tw/ntnujava/

## Easy Java Simulations (2001- ) => Dynamics => Topic started by: Fu-Kwun Hwang on February 20, 2010, 11:22:34 am

 Title: Perfectly inelastic collision Post by: Fu-Kwun Hwang on February 20, 2010, 11:22:34 am In a perfectly inelastic collision, the colliding particles stick together.Assume there are two particles with mass and velocity as $m_1, \vec{v_1}$ and $m_2,\vec{v_2}$If the velocity after the collision is $\vec{u}$From conservation of momentum, $m_1\vec{v_1}+m_2 \vec{v_2}=(m_1+m_2)\vec{u}$So $\vec{u}=\frac{m_1\vec{v_1}+m_2 \vec{v_2}}{m_1+m_2}=V_{cm}$Energy loss due to collision is$\Delta k=\frac{1}{2}m_1 \vec{v}_1^2 +\frac{1}{2}m_2 \vec{v}_2^2 -\frac{1}{2} (m_1+m_2) \vec{u}^2=\frac{1}{2}\frac{m_1m_2}{m_1+m_2}(\vec{v}_1-\vec{v}_2)^2$