Since force is related to a change in momentum and not necessarily just to a change in velocity, what would be an example where only the mass of a body changes but not its velocity when subjected to a force?

Question

Since force is related to a change in momentum and not necessarily just to a change in velocity, what would be an example where only the mass of a body changes but not its velocity when subjected to a force?

In: Physics

Answer 1

My first thought was particle accelerators where the particles are close to the universal speed limit and will therefore not go any faster no matter how much acceleration you give them but will instead increase in mass. However /u/LordSpazpatty is completely right with the hovering rocket example as well as the mass is reduced due to fuel being burned by the engines requiring less force to keep the same acceleration.