No quiz today - just a positive mass and negative mass in orbit, with a r^0 force law.
https://www.testtubegames.com/gravity.html?lvl=eNpFzrEOAjEIgOHXuYEjUEpbuF1XZweNcT1joubivb2tPSMLYfi-cH4OsNv740Tw9tEwKZkwrD6yYDZKAY5OaH2mywA3ZyKC6332AHNfB295EpSkZq0uBQOrCSyVJSRpuTIsqzOW0i54OXVw1A2MHYwV5ApyEOTy5bC6lvTH5T9X38wbFyPG6QNiUTOt
Fling planets and change physics in this gravity sandbox. Want to add 1000 planets? Go ahead. Curious about Lagrange Points? Make em. Hate the inverse square law? Change it.