The space probe Rosetta was designed to investigate a comet. The probe consisted of an orbiter and a lander. The orbiter had a mass of 170 kg and the lander had a mass of 100 kg. When the two parts separated, the lander was pushed towards the surface of the comet so that its change in velocity towards the comet was 3.0 m s⁻¹. [Figure showing an orbiter (mass 170kg) and a lander (mass 100 kg) separating, with lander's velocity change 3.0 m s⁻¹] Assume that the orbiter and lander were an isolated system. The orbiter moved away from the comet during the separation. What was the change in the speed of the orbiter?

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