Which of the following quantities must remain constant for a nonrigid body when no external force acts upon it?

Step-by-step solution

According to Newton's second law, the rate of change of linear momentum is equal to the net external force applied to the system, F _ ext = d p dt . Since no external force acts on the body, F _ ext = 0 , which implies p = constant . Thus, linear momentum must remain constant. The absence of any external force also implies that the net external torque acting on the system about any point is zero, _ ext = 0 . Since _ ext = d L dt , we get L = constant . Thus, angular momentum must also remain constant. For a nonrigi