Why is acceleration regulated by mass? In a frictionless environment, why doesn't an object move at infinite acceleration if force is applied on it?
Force causes movement, so unless there is an opposing force there shouldn't be any reason for the force to cause infinite acceleration.
Why does mass act like an opposing force that limits the acceleration caused by an force to less than infinity?
Best Answer
That's just the way the world is. The fact that the resultant force $F$ on an object is proportional to the object's mass $m$ and its acceleration $a$, i.e. $$F=ma,$$ is a fundamental principle and cannot be derived from anything else (unless you count minimum-action principles and fancier, but equivalent, formulations of classical mechanics, or you see newtonian mechanics as emerging from quantum mechanics, which of course QM was built to do).
Mass does not "act as an opposing force". In newtonian mechanics, mass translates between forces and accelerations and accounts for the fact that different bodies respond differently under the same circumstances (i.e. when subjected to the same forces). Thus as far as classical mechanics is concerned, Newton's second law defines (inertial) mass.