How Far?
•position:
The location of an object
•symbol: x
• distance:
– symbol: d
– units: meters

• displacement:
d
– symbol:
– units: meters

d
How far an object has
traveled
How far an object is from it’s
initial position
Is a “vector” quantity
A vector quantity has magnitude AND direction
A plain, old quantity is called a SCALAR
Our first Equations!!!
• Displacement is the difference between
an object’s initial position and where it
winds up.
– We’ll call initial position:
xi
– So we’ll call final position:
xf
– Therefore,

d  x f  xi
Motion Intro
SpeedThe rate of distance traveled over time
d
symbol: v
v
meters
m
units: sec ond or sec
t
Velocity- the rate of displacement done over time
the rate of change in position over time

symbol:
 d
v
units: meters
m
t
or
sec ond
sec

v
Motion Graphs
At the end of the stomper lab there were
two graphs
•The blue graph, of the
stomper car going forward,
has a positive slope
•The red graph, of the car
going backward, has a
negative slope
•Slope has the same value,
just opposite sign
So, is the slope of a position vs. time graph speed,
or velocity?
Motion Maps
• You made one in the Stomper Car Lab:
– It shows the position of an object in motion at
equal time intervals
v1
v2
v3
v4
v5
0 sec
1 sec
2 sec
3 sec
4 sec
5 sec
1. Label your position marks, starting with 0 s (we’ll assume
time in seconds)
2. Draw an arrow (velocity vector) from one position to the
next
3. Label that 1st vector as v1
4. Repeat for following velocities
Handy Advice

1. Take our
 d
xf  xi
velocity
v
equation
t t
2. Substitute in for

displacement
d  xf  xi
3. Solve for “xf”