Ch 1 (Etkina) Notes Flashcards
When describing motion, we need to focus on two important aspects: the … whose motion we are describing (the …) and the … who is doing the describing (the …)
object; object of interest; person; observer
Motion is a change in an object’s …. relative to a …. during a certain change in ….
position; given observer; time
Without identifying the observer, it is impossible to say whether the object of interest
moved
physicists say motion is …., meaning that the motion of any object of interest depends on the …. of the observer
relative; point of view
people intuitively use … as the object of reference- the object with respect to which they …
earth; describe motion
what we view as the object of reference influences how we
describe motion
specifying the observer before describing the motion of an object of an interest is an extremely important part of constructing what physicists call a
reference frame
a reference frame includes an …, a …. with a … for measuring …, and a … to measure …
object of reference; coordinate system; scale; distances; clock; time
if the object of reference is large and cannot be considered a point-like object, it is important to specify where on the object of reference the … of the coordinate system is placed
origin
(reference frame includes) an object of reference with a specific …. on it
point of reference
(reference frame includes) a coordinate system, which includes one or more …., and an …. located at the … it also includes a … for specifying … along the xes
coordinate axes; origin; point of reference; scale; distances
(reference frame includes) a clock which includes an … called … and a unit of measurement for specifying … and ….
origin in time; t=0; time; time intervals
one-dimensional/linear motion is a model of motion that assumes that an object, considered as a …., moves along a …
point-like object; straight line
when the object travels at constant speed, the dots are
evenly spaced
when the object slows down, the dots get
closer
when the object moves faster and faster, the dots get
farther apart
we can represent motion in even more detail by adding … to each dot that indicate which … the object is moving and how … it is moving as it passes a particular position
velocity arrows; way; fast
dot diagrams + velocity arrows is
motion diagram
the longer the arrow, the … the motion
faster
vectors have … and …
direction; magnitude
velocity change arrow (Δv→) indicates change in … on …
velocity; motion diagram
a velocity change arrow is a … indication
qualitative
a velocity change arrow points in the same direction as the velocity arrows when object is …. it points in the opposite direction when the object is …
speeding up; slowing down
when velocity changes are the same for each time interval, all of the velocity change arrows will be the …, so we only need use … for the whole motion diagram
same length; one
time described in two ways:
time: the … clock reading
time interval (…): the … clock readings
actual; Δt; difference in
time and time interval are
scalar quantities
position: object’s … with respect to the …
location; coordinate system