Final answer:
Fuel jettisoning is done by ejecting spent fuel from a spacecraft, typically a rocket, after it has been used for propulsion. This process follows Newton’s Third Law of Motion and doesn’t require an external force.
Step-by-step explanation:
The original question appears to have a typo. If the question is 'Fuel jettisoning is usually accomplished', it seems it is inquiring how the process of fuel jettisoning, or discarding excess fuel, is implemented. In the context of rockets and space travel, this typically occurs when the fuel has been consumed to thrust the spacecraft and is then ejected out. Rockets use fuel mixtures - either liquid or solids, which are ignited to start the chemical reactions generating thrust.
This jettisoning of the fuel follows Newton’s Third Law of Motion: 'For every action, there is an equal and opposite reaction.' The action is the expulsion of gas behind the rocket, and the reaction is the movement of the rocket in the opposite direction. Since no external force is required to set an object in motion in outer space, a rocket can continue to travel in a straight line until acted upon by another force — for example, the gravitational pull of another celestial body
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