An unmanned interstellar vessel is traveling through deep space where there is no atmosphere. Initially, it is moving at a constant speed in a straight line.
State whether a continuous force is necessary to keep the vessel moving at this constant speed.
The vessel's rear ion engines are now turned on, ejecting high-speed exhaust gases directly backward. State the effect of this action on the motion of the vessel.
Eventually, the vessel enters the atmosphere of a gas giant planet with its engines turned off. Under these conditions, suggest two physical effects that the atmosphere has on the vessel.
245 exam-style questions on CIE IGCSE Physics 1.5 Forces, covering 1.5.1a Forces, resultant force and motion, 1.5.1b Load–extension graphs and the spring constant, 1.5.1c Friction and drag, 1.5.1d Force, mass and acceleration, 1.5.1e Motion in a circular path, 1.5.2a Moment of a force, 1.5.2b Principle of moments and equilibrium, and 1.5.3 Centre of gravity and stability. Each one has a worked solution and a mark scheme showing where the marks go.