Question 2381
What physical quantity is conserved when external force is zero?
Question 2382
What is the trajectory of a free particle?
Question 2383
In a two-body decay with center of mass at rest, what is the relationship between the momenta of the products?
Question 2384
Why is the center of mass frame useful in studying radioactive decay?
Question 2385
What happens to the total momentum vector in an isolated system?