Module 1: An Introduction to Motion Flashcards
motion diagrams
the composite image shows an object’s positions at several equally spaced instants of time
two step process for solving motion problems
- representation
- analyze with the language of mathematics
motion
the change of an object’s position/orientation with time
trajectory
the path along which an object moves
4 basic types of motion `
- straight line motion
- circular motion
- projectile motion
- rotational motion
a video camera takes images at a fixed rate. each separate image is called a…
frame
motion diagram
the composite image shows an object’s positions at several equally spaced instants of time
operational definitions
the concepts are defined in terms of a particular procedure or operation
constant speed motion diagram
images that are equally spaced
speeding up motion diagram
there is an increasing distance between the images
slowing down motion diagram
there is a decreasing distance between the distance
more complex motion diagrams show changes in…
speed and direction
oscillating system
something that moves back and forth around an equilibrium position (examples: vibrating guitar string, sound wave, jiggling atoms in a crystal)
modeling
stripping away the details to focus on essential features
model
a highly simplified picture of reality, but still captures the essence of what we want to study
descriptive models
what are the essential characteristics and properties of phenomenon? how do we describe it in the simplest possible terms?
explanatory models
why do things happen as they do?
predictive power; allow us to test whether a model gives an adequate explanation of our observations
t/f: the motion of the object as a whole is not influenced by the details of the object’s size and shape
true
for the purpose of analyzing motion, we often consider the object as if it were just a…
single point
particle
an object that can be represented as a mass at a single point in space
simplifying a motion diagram using the particle model
the particle model
allows us to see connections that are very important but that are obscured or lost by examining all the parts of an extended, real object
t/f: all objects falling under the inlfuence of gravity move in a different manner if no other forces act
false; all objects falling under the influence of gravity move in exactly the same manner if no other forces act
the particle model for two falling objectts
one dimensional motion
the motion of an object that can move only along a straight line
position
your location at a particulat instant in time
origin
reference point from which all distances are to be measured
describing your position
in order to specify how far out object is from the origin, we lay down… along the line of the objects motion
an imaginary axis
coordinate system
an origin and an axis marked in both the positive and negative directions can be used to unambiguously locate the position of an object
the coordinate system used to describe objecys along a country road
coordinate
the symbol that represents a position along an axis
a coordinate system for a 50 meter race
examples of one dimensionsal motion
the motion diagram of a car that travels at constant speed and then brakes to a halt
sam undergoes a displacement △x from position xi to position xf
displacement
a change of position
the change in any quantity is…
the final value of the quanity minus its inital value
signed quantity
it can be wither positive or negative
t/f: displacement is a signed quantity
true
a displacement is a signed quantity. here △x is a negative number
time intervals
changes in time
the motion diagram of a bicycle moving to the right at a constant speed
a time interval (△t) measures…
the elapsed time as an object moves from an initial position xi at time ti to a fianl position xf at time tf
uniform motion
motion at a constant speed
motion diagrams for a car and a bicycle
t/f: the smaller the distance traveled by an object in a given time interval, the greater its speed
false; the greater the distance traveled by an object in a given time interval, the greater its speed
speed of an object
speed = (distance traveled in a given time interval) / (time interval)
two bicycles traveling at the same speed, but with different velocities
velocity of a moving object
velocity = displacement / time interval = △x / △t
speed vs. velocity
speed measures how fast an object moves; velocity measures an object’s speed and direction
instantaneous velocity
the velocity of an object at a particular instant in time
per
associates the number of units in the numerator with one unit of the denominator
