A cart rolls toward a rigid wall with negligible track friction
PHYSICS · Single correct · CBSE · Physics · Laws of Motion · Laws of Motion
Problem
A 0.50kg cart rolls toward a rigid wall with negligible track friction. A student defines the system to be the cart alone. During the brief interval while the cart’s spring bumper is compressed against the wall, which statement best describes whether the linear momentum of the system is conserved?
(a) Yes, because the forces during the collision are equal and opposite and therefore cancel, so the net force on the cart is zero.
(b) No, because kinetic energy is not conserved while the spring is compressed.
(c) No, because the wall exerts an external force on the cart during contact.
(d) Yes, because the collision interval is so short that any external impulse can be neglected.