Learn the science
Make the physics statement specific
A correct claim is that a moving object following a uniform circular trajectory requires a net force directed toward the circle's center; its magnitude is mv²/r. This is a resultant of actual interactions, which may be friction, tension or gravity depending on the physical case. It is incorrect to say that a constant-speed circular object has no acceleration.
Cite two different calculations
Choose m=2 kg, v=4 m/s and r=8 m: a_c=2 m/s² inward, F_net=4 N inward. At doubled speed v=8 m/s with the same radius, F_net rises to 16 N. Then use a friction example: for m=5 kg, μ_s=0.4 and g=9.8, the static limit is 19.6 N, but a 12 N applied push is opposed by only 12 N when the block remains at rest.
Address alternative explanations
A model of a tethered puck and a model of a car on a level road can both display circular motion, yet different forces provide their inward net force. A student might mistakenly add F_c separately to the tension arrow. Another might treat f_s,max as an always-on force rather than a bound. Correct both errors explicitly by naming force agents and comparing numeric predictions.
Report uncertainty and human assessment boundaries
These labs use idealized mathematical data. They cannot certify a real friction coefficient or predict safe speeds. Finish with the assumptions, one plausible deviation and an improvement to your method. Friday randomly presents 10 of 20 public open-book questions; its feedback and browser-local score are formative, not confidential midterm/final results.