Newton’s second law accurately predicts changes in the
motion of macroscopic objects. (HS-PS2-1)
Momentum is defined for a particular frame of reference;
it is the mass times the velocity of the object. (HS-PS2-2)
If a system interacts with objects outside itself, the total
momentum of the system can change; however, any
such change is balanced by changes in the momentum of
objects outside the system. (HS-PS2-2),(HS-PS2-3)