Pls help, sorry for the trouble

Question

Link to image of the problem

Thank you!

Answer 1

In the frame of reference of the cart, the center of mass is, and remains, exactly halfway between the rolling objects since they are identical and approaching each other at the same speed. In this frame of reference the center of mass velocity (v_cm) is:

v_cm = v_b – v_b = 0

In the frame of reference of a person standing at rest alongside the cart, the center of mass moves at the same speed as the cart:

v_cm = v_c

Multiple Choice Answer (in the figure):

Train: Zero; Person: v_c to the right