Dear Manitunc, My point is that you cannot make the general statement that a heavy tonearm is "better" than a light one, or vice versa, because there are other factors involved and for sure there are conditions within which either proposition is the correct one. And the model of a cartridge held static in space is a bad one to start from, I still say.
"An object in motion tends to stay in motion". Yes, that is inertia.
"Momentum" is a quantity applicable to a body in motion. Momentum is equal to mass X velocity. Inertia also says that a body at rest will tend to stay at rest. A body at rest has no momentum.
"An object in motion tends to stay in motion". Yes, that is inertia.
"Momentum" is a quantity applicable to a body in motion. Momentum is equal to mass X velocity. Inertia also says that a body at rest will tend to stay at rest. A body at rest has no momentum.