Re: Cause and Effect

["D.V.N.Sarma" <narayana@HD1.VSNL.NET.IN>]

> > The concept of force mainly arises from the subjective experience
> > of pushes and pulls.
> >
> > The awareness of acceleration is not subjective.
>
> Force is measurable.
> Acceleration is measurable.
> I don't consider one more subjective than the other.

Fundamental quantities are chosen in such a way
that they are readily understood intuitively. As a matter of
fact some people prefer to replace mass by force in the
fundamental quantities because force is understood more intuitively
than mass. Force you can feel directly and mass is judged only
by resistance it offers when we try to move it. Force concept is
definitely more subjective and intuitively understood than
acceleration. I do not think there can be any two opinions about
this because this is  a matter of experience of all of us.
Acceleration by all accounts is a derived quantity L/T*2.

No doubt force can be measured but it also can be felt.
Acceleration cannot be felt, it can only be measured.

As a matter of fact I have once posted a letter to this list
saying that motion (not acceleration) is more fundamental than
time. Because without motion there is no time. When
nothing happens, there are no events and there is no time.

Hope this helps.

regards,

Sarma.
> > Therefore since we have to proceed from known to the unknown,
> > force causes acceleration is only thing that is understandable and
> > not vice versa.
>
> We can know force without acceleration, by observing the extension of a
> calibrated spring.  This is the usual starting point for a pedagogical
> operational definition of force.  There is nothing subjective about it.
>
> Is it common to tell students that force must be understood in terms of
> acceleration?  I wasn't taught that way, and until this moment it never
> occurred to me that anyone might teach that.
>
> Also note that the direction mentioned above (from allegedly more known
> acceleration to allegedly less known force) suggests that acceleration
> comes before force, i.e. that acceleration causes force, which is
> diametrically
> opposite to the point that was being advocated.