B.5.MPC.R:3 - Forces

Force	Tension
Local correctness and joint usefulness	A valid result can answer a question different from the receiving physical question.
Stable relations and changed unknowns	The same physical relation can serve several questions, but each may require a different computation.
Observation and intervention	Obtaining an indication can change the state or conditions whose behavior is being inferred.
Economical repair and unresolved alternatives	A short correction can suffice; an ambiguous discrepancy may need a discriminating observation or a conditional result.
Useful abstraction and realizable operation	Mathematical possibilities can exceed the preparation, timing or range of the available apparatus.