Question

Why do we take readings only in the steady state ?

Answer 1

Because dear
we take the observations
only in the steady state
because in steady state
no heat is absorbed
by the metal bar
and
amount of heat conducted
theough any section
of bar is same

Answer 2

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$\purple{here \: is \: your \: ans:}$
For such a steady state to develop, the system does not have to be a flowsystem. Therefore, such a steady state can develop in a closed system where a series of chemical reactions takeplace. Literature in chemical kinetics usually refers to this case, calling itsteady state approximation.
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