Question

Peter (80 kg) stands on one end of a 5.0 m long cart (40 kg) that can roll perfectly on a horizontal surface. The cart and Peter are initially at rest. After Peter runs to the opposite end, the cart moves to the left. How much does the center of mass of the Peter + cart system move?

A) 4.0 m to the left
B) 2.5 m to the left
C) 0
D) 2.5 m to the right
E) 4.0 m to the right

Answer 1

The center of mass of the system, composed of Peter and the cart, remains unchanged because there are no external forces, so the center of mass does not move as a result of Peter running across the cart. option c is correct

Step-by-step explanation:

option c is correct The center of mass of a system will not move if the system is closed and isolated, meaning there are no external forces acting on it. In the scenario where Peter runs from one end of the cart to the other, the cart moves in the opposite direction to preserve the center of mass of the system. Assuming no external forces, the center of mass remains in the same position before and after Peter's movement, and hence the answer would be C) 0.