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When you push an object with your finger there is a long history of
thoughts and actions that culminate with you placing your finger on
the object and an acceleration of that object.
I think a poll of most people would result in an interpretation of
the word "caused" in this case to be that the finger caused the
object to move
It is often stated that physicists build models of reality. A model
which states that acceleration is always caused by a net force
seems to be very useful. That is what Sarma would say about the
a=F/m. The mass of an object, in a classical model, does not depend
on speed. But the m must known to calculate the a(t) when a
particular F(t) is given. Do I interpret him correctly?
Yes, a mathematician can write the second law as F=m*a, or m=F/a.
That does not contradict the useful model of a physicist--in order
to accelerate an object one needs a net force. Causality is part
of the model, it is not part of reality.
Yes, I know that more general models can be, and have been,
created. All models have limited validity. The simplest model is
appropriate in teaching introductory physics courses.
Yes, a mathematician can write the second law as F=m*a, or m=F/a.
Learning about more general models, in advanced classes, does not
mean "unlearning of what has already been learnt."