Answer:
Step-by-step explanation:
work done by the child = force x displacement
= 32 x 6 = 192 J
This energy would have been added to the two body system ( two wagons ) in the form of kinetic energy . Initially the kinetic energy of the system was zero . The final kinetic energy of the system
= 0 + 192 J = 192 J
So change in the kinetic energy of the system
= 192 - 0 = 192 J .