When two elastic bodies collide, which law helps to determine the resulting velocity?

When two elastic bodies collide, the determination of the resulting velocity is governed by both the conservation of momentum and the conservation of energy principles.

In an elastic collision, kinetic energy is conserved before and after the collision. This means that the total kinetic energy of both bodies combined remains the same throughout the event. The conservation of energy principle is integral for understanding how energy is transferred between the colliding bodies without any loss to heat or deformation.

Additionally, the conservation of momentum states that the total momentum of the system (the combined mass of both elastic bodies) before the collision must equal the total momentum after the collision. This occurs because external forces are negligible during the short moment of impact, and therefore, the momentum of the system remains constant.

By applying both conservation equations, one can effectively determine the resulting velocities of the two bodies post-collision, given their initial velocities and masses. This is essential in solving problems related to collisions in physics and engineering, especially in machine design contexts where understanding the interaction between moving parts is critical for performance and efficiency.