I keep getting “Archimedes' principle” questions wrong in Mechanical Properties of Fluids. What's the trap?
comparing the object's total weight instead of its average density with the fluid's.
The usual trap: comparing the object's total weight instead of its average density with the fluid's. How to avoid it: floats if average density < fluid density; sinks if greater. Go back to the definition — a submerged body feels an upward buoyant force equal to the weight of the fluid it displaces.
Key point
Archimedes' principle
Common mistake
comparing the object's total weight instead of its average density with the fluid's.
Memory tip
floats if average density < fluid density; sinks if greater.
Tap to watch or see it right here — the app stays open (it only opens a quick search if nothing embeddable is found).