Pendulum Collision

This interactive simulator explores Pendulum Collision in Classical Mechanics. Two bobs: hit along normal, e elastic; θ¨ between hits vs 1D collisions. Use the controls to change the scenario; watch the visualization and any graphs or readouts to connect the model with lectures, labs, and homework.

Who it's for: Best once you already know the basic definitions and want to build intuition. Typical context: Classical Mechanics.

Key terms

  • pendulum
  • collision
  • pendulum collision
  • mechanics
  • classical

Live graphs

How it works

Two equal-length pendulums hang from nearby pivots. While the bobs are in contact we treat them like smooth spheres: resolve velocities into components along the line of centers (normal) and tangential to that line. The normal components undergo a one-dimensional collision with restitution e (e = 1 is elastic); tangential components are unchanged, so no rotational dynamics are modeled. Between hits each bob is a simple planar pendulum. For e = 1 total kinetic energy is conserved at each impact; horizontal momentum is not exactly conserved in the full 2D problem because the pivots exert forces, but the graphs track the sum of horizontal bob momenta as a qualitative check.

Key equations

v₁n′, v₂n′ same as 1D · v_t unchanged · ω = (v·t̂)/L
Pendulum: θ¨ = −(g/L) sin θ between collisions