An astronaut of mass and a wrench are initially at rest relative to a nearby spacecraft
PHYSICS · Single correct · CBSE · Physics · System of Particles and Rotational Motion · System of Particles and Rotational Motion
Problem
An astronaut of mass 80kg and a 5kg wrench are initially at rest relative to a nearby spacecraft. The astronaut throws the wrench straight forward at 10ms−1 relative to the spacecraft. Which statement about the motion of the center of mass of the astronaut–wrench system relative to the spacecraft is most consistent with physical principles?
(a) The center of mass moves forward at approximately 0.6ms−1 because the lighter wrench carries most of the momentum.
(b) The center of mass moves backward at about 0.6ms−1, following the heavier astronaut’s recoil.
(c) The center of mass remains at rest because no net external force acts on the system.
(d) The center of mass moves forward at 10ms−1, the same speed as the wrench.