Tag
Dynamics
Entries tagged dynamics.
6 entries
Action-reaction pairs
Every force one object exerts on a second is matched, at the same instant, by an equal and opposite force the second exerts back on the first, and this pairing is what makes pushing off anything, including empty exhaust gas, actually work.
7 min
ConceptForce as interaction
A force is not a substance an object carries; it is what one object does to another during an interaction, and every force names a specific pair and a specific cause.
7 min
ConceptMass as resistance to acceleration
Mass is not how much stuff an object has or how big it looks; it is a measured resistance, how much acceleration a given force fails to produce.
7 min
ConceptThe relation between force, mass, and acceleration
Net force, mass, and acceleration are locked together by one relation, net force equals mass times acceleration, and it can be reconstructed, not just memorized, from how force and mass were separately defined.
7 min
ConceptUniversal gravitation
Every two masses in the universe pull on each other with a force that grows with both masses and falls off as the square of the distance between them, the same law that governs a falling apple and a moon in orbit.
8 min
ConceptWeight and gravitational interaction
Weight is not a property an object owns; it is the specific gravitational force pulling on it right now, which is why the same object weighs differently on the Moon, in an accelerating elevator, and in orbit, while its mass never changes at all.
7 min