An eccentric impact is an impact that occurs off of the center of mass of a rigid body. This impact will in turn cause the mass to rotate, while if the impact occurred on the same line as the center of mass then the rigid body would only have translational motion.

As with any type of impact the coefficient of restitution has an effect on the velocities after the impact occurs. To view the equation to calculate the coefficient of restitution refer to equation 1.

**(Eq 1) **$θ=\frac{∫Rdt}{∫Pdt}=\frac{ϖ_{B_2}-ϖ_{A_2}}{ϖ_{A_1}-ϖ_{B_1}}=\frac{v_{B_2}-v_{A_2}}{v_{A_1}-v_{B_1}}$