MOTION DURING EQUILIBRIUM Time is always on the side…

REVIEW We have seen so far 2 types of motion, both related to a type of equilibrium. In both motions, there is a kinematic variable that remains constant. For now, we will stick to translational motions.

TRANSLATIONS EQUILIBRIUM MOTION static dynamic @ rest uniform

TRANSLATIONS EQUILIBRIUM MOTION static Dynamic @ rest Uniform Constant kinematic variable Dynamic @ rest position Uniform velocity

Kinematic Variables From kines- – motion. Used to describe the motion of the object over time. They are position, velocity and acceleration. Acceleration is the rate of change in velocity. Acceleration will only be present if impulse is present.

MOTION GRAPHS Kinematic variables are used to graphically show motion and changes in motion over time. The 3 possible graphs are: position-time, velocity-time and acceleration-time graphs. In motion graphs, time is always in the x-axis.

OBJECT @ REST Position never changes. Position is constant. Position is the location of the object relative to a reference point. Because the position never changes, the velocity of an object at rest is also zero.

Object at rest d v ? ? t t

Object at rest d v ? t t

Object at rest d v 0 t 0 t

Object in Uniform Motion d v ? ? t t

Object in Uniform Motion d v ? t t

Object in Uniform Motion d v 0 t 0 t

Position-time Graphs d v slope? 0 t 0 t

Position-time Graphs d v slope = rise over run 0 t 0 t

Position-time Graphs d slope = ∆𝑑 ∆𝑡 v 0 t 0 t

Position-time Graphs d slopv = ∆𝑑 ∆𝑡 v 0 t 0 t

Position-time Graphs To go from… to… d v find slope a 0 t 0 t

MOTION GRAPHS Object @ rest Uniform Motion ? d v a 0 t 0 t 0 t

MOTION GRAPHS Object @ rest Uniform Motion ? d v a 0 t 0 t 0 t

MOTION GRAPHS Object @ rest slope slope Uniform Motion ? slope slope ? d v a slope slope ? 0 t 0 t 0 t Uniform Motion slope slope ? 0 t 0 t 0 t

THAT’S ALL, FOLKS… … FOR TODAY.