Tag
Kinematics
Entries tagged kinematics.
7 entries
Acceleration
Acceleration is the rate of change of velocity, and because velocity has both a size and a direction, an object accelerates whenever it speeds up, slows down, or merely changes direction, even at constant speed.
7 min
ConceptInertia and the persistence of motion
Inertia is the tendency of an object to keep whatever velocity it already has, constant speed in a constant direction, unless something acts on it to change that velocity, which means force is needed to change motion, not to maintain it.
7 min
ConceptLevers, linkages, cams, and motion conversion
A lever, linkage, or cam uses pure geometry, not motors or electronics, to transform a given force or motion into a different force or a different, deliberately chosen path.
7 min
ConceptMotion graphs
Position time, velocity time, and acceleration time graphs are three pictures of the same motion, connected because slope on one graph gives the value plotted on the next, and area under one gives the change plotted on the graph before it.
7 min
ConceptPosition, distance, and displacement
Position is where something is relative to a chosen origin, distance is the total length of the path travelled, and displacement is the straight, directed change between start and end, and the three are related but never interchangeable.
7 min
ConceptSpeed and velocity
Speed is how fast the distance odometer is ticking, a plain number with no direction, while velocity is the rate of change of displacement, a directed quantity that can be zero, positive, or negative even while speed stays constant.
6 min
ConceptTwo-dimensional motion and projectiles
Motion in two dimensions, including a thrown or launched projectile's curved path, can be built exactly by treating the horizontal and vertical motions as two independent one-dimensional motions happening at the same time, sharing only the clock.
7 min