Important Physics Topics By guyster Period: Jan 1, 1100 to Jan 1, 1165 Hibat Allah Abu'l-Barakat al-Baghdaadi: Force and acceleration He proposed that force is proportional to acceleration and not velocity Jan 1, 1121 Al-Khazini: Gravitational Potentiel Energy Develops the concept of gravitational potentiel energy and the idea that gravity is a force acting at a distance
