1) A rocket system can be modeled using Newton's Second Law of Motion. The thrust of a rocket is equal to the rate of change of momentum. 2) For a rocket of initial mass m drifting at velocity V0, the thrust is equal to the rate at which exhaust gases are ejected multiplied by the exhaust velocity. 3) The thrust equation relates the thrust of a rocket to the mass flow rate and exhaust velocity, where thrust equals the mass flow rate times exhaust velocity.