PHY.6:4.6 - Derive the consequence and return through the implicated premise

Obtain the first result at the resolution the question needs. This may be an initial derivative, an integrated balance, a limiting state or a computed evolution. B.5.MPC connects the mathematical result and its conditions to the physical question.

Use checks that can distinguish a wrong construction for this use. Combining part balances can expose a duplicated exchange; an energy calculation can expose a sign error or an omitted conversion; substituting the preparation can expose an impossible constraint. A limiting case or available observation can test a disputed physical premise. Passing one such check establishes only what it examines.

Distinguish a consequence of the stated equations from evidence that those equations describe the intended situation. Numerical accuracy concerns how the chosen consequence was obtained. Physical adequacy concerns the premises, preparation and interactions represented. Keep those qualifications with the result, without requiring new evidence when the conditional result already serves the work.

When the question, preparation or connection changes, revisit the affected relations. Retain contributions whose conditions still hold. An unresolved exchange law directs work to physical theory or response characterization; inconsistent coupled quantities direct work to the connection; an adequate account with an inaccurate computed result directs work to the computation. B.5.MPC.R supplies the broader repair when physical, mathematical and computational contributions need to change together.