PHY.1:4.5 - Resolve a mismatch by its effect on the answer

If the conditions conflict, identify which physical contribution changes and how that could change the requested result. The conflict can itself rule out the proposed experiment at the chosen settings.

Choose the next move from the remaining physical possibilities. You can change a free setting, construct a different arrangement, retain a simpler physical regime, or derive how the unmatched contribution modifies the output. If several mismatched experiments are to be combined, construct the relation that permits that combination; a fitted relation retains its assumptions and the range over which it can be used. MMP.9 and MMP.11 can supply reduction and constrained model construction for these returns.

A small coefficient can support an approximation when its influence on the output is controlled. Inspect where that argument could fail. Thin boundary layers, a threshold, resonance or a long observation interval can make a nominally small contribution consequential. Derive a useful bound, compare an applicable limiting solution, or obtain a discriminating observation when it can settle the use. C.29.1 carries a bound through the later inference.

Use an existing result when it resolves the mismatch at the required strength. A conditional result or a limit can be enough. Additional measurement is selected by what its possible answers would change, including its cost, through C.11.DUA.