Name____________________________________ Section_____________ Date__________
CONCEPTUAL PHYSICS: Hewitt/Baird
Linear Motion
Tech Lab
Motion Graphing Simulation
Motivating the Moving Man
Purpose
To
study
one‐dimensional
motion
through
the
use
of
a
computer
simulation
Apparatus
computer
PhET
simulation:
“Moving
Man”
(available
at
http://phet.colorado.edu)
Setup
1.
Turn
the
computer
on,
log
on
and
allow
it
to
complete
its
start
up
cycle.
2.
Find
and
start
the
PhET
Simulations
and
run
the
Moving
Man
simulation.
Ask
your
instructor
for
assistance
if
needed.
3.
Locate
the
time‐scale
expansion
button.
Time
is
the
horizontal
axis,
not
the
vertical
axis.
Use
the
time­scale
expansion
button
to
expand
the
time
axis
so
that
only
10
seconds
can
be
seen.
4.
Find
and
use
the
buttons
that
will
delete
the
velocity
vs.
time
and
acceleration
vs.
time
graphs.
You
are
left
with
one
graph:
position
vs.
time.
And
its
horizontal
axis
now
runs
from
only
0
to
10
seconds.
5.
Set
the
computer
aside
and
read
the
Discussion
section
below.
When
you
have
finished
reading
the
Discussion,
continue
with
the
activity.
Discussion
The
simulation
provides
us
with
a
simple
interface
we
can
use
to
study
motion
graphs.
Specifically,
we
can
control
the
position,
velocity,
and
acceleration
of
an
object
and
see
the
graphs
of
position,
velocity,
and
acceleration
of
that
object.
The
simulation
allows
us
to
manually
control
the
object
by
dragging
it.
We
can
also
drag
a
position
“slider”
control.
More
importantly,
we
can
set
initial
conditions
for
the
object
then
let
its
motion
proceed.
We
can
pause
the
motion,
and
the
motion
is
limited
in
space
by
the
walls.
Procedure
Step
1:
Complete
the
matching
exercise
on
the
next
page.
The
names
of
many
objects
and
buttons
are
listed.
Draw
a
line
connecting
the
name
of
each
object
or
button
to
the
object
or
button,
itself.
Your
screen
and
Figure
1
should
be
very
similar
in
that
only
the
position
vs.
time
graph
is
visible
and
that
the
horizontal
(time)
scale
runs
from
0
to
10
seconds.
PhET
simulations
are
revised
from
time
to
time,
so
some
elements
of
the
screen
layout
may
have
changed.
Step
2:
Manual
Man
a.
Click
on
the
man
and
drag
him
in
the
positive
direction
(toward
the
house)
at
a
steady
rate
of
1
m/s
to
the
best
of
your
ability.
Your
graph
won’t
be
perfect
(limitations
of
the
computer’s
interface
prevent
this),
but
try
to
move
the
man
as
smoothly
as
you
can
at
1
m/s.
b.
While
the
graph
is
still
on
the
screen,
click
the
on‐screen
button
to
show
the
velocity
vs.
time
graph.
This
graph
plots
the
value
of
the
velocity
as
time
passes.
Clear
the
graphs
and
try
again.
Move
the
man
manually
from
0
to
10
meters
in
10
seconds—as
smoothly
as
possible—at
1
m/s.
The
simulation’s
“stopwatch”
reading
indicates
time.
More curriculum can be found in Pearson Addison Wesley‘s Conceptual Physics Laboratory Manual:
Activities · Experiments · Demonstrations · Tech Labs by Paul G. Hewitt and Dean Baird. ISBN: 0321732480
More curriculum can be found in Pearson Addison Wesley‘s Conceptual Physics Laboratory Manual:
Activities · Experiments · Demonstrations · Tech Labs by Paul G. Hewitt and Dean Baird. ISBN: 0321732480
c.
Sketch
the
resulting
position
vs.
time
and
velocity
vs.
time
graphs
on
the
graphs
page
at
the
end
of
this
write‐up.
Step
3:
Programmed
Man
a.
Make
sure
the
position
and
velocity
graphs
are
showing
(with
the
time
scale
set
from
0
to
10
seconds)
and
the
acceleration
graph
is
hidden
(deleted).
Clear
the
graphs.
b.
Set
the
initial
position
of
the
man
to
0
m.
(Use
the
slider
or
type
it
into
the
value
box.)
c.
Set
the
initial
velocity
of
the
man
to
+1.0
m/s.
(Use
the
slider
or
type
it
into
the
value
box.)
d.
Click
an
on‐screen
Go
button
and
observe
the
resulting
motion
graphs.
Sketch
both
graphs
(position
vs.
time
and
velocity
vs.
time)
on
the
graphs
page
at
the
end
of
the
lab.
e.
Clear
the
graphs.
Set
the
initial
velocity
of
the
man
to
+2.0
m/s
and
run
the
simulation
again.
The
motion
ends
when
the
man
hits
the
wall.
Stop
the
simulation
when
that
occurs.
Disregard
data
from
the
wall
impact
and
beyond.
Describe
two
differences
in
the
position
vs.
time
graph.
(Hints:
rise/run;
duration.)
f.
Add
lines
to
your
previous
sketch
representing
the
+2.0
m/s
motion.
Be
sure
to
label
both
lines
now
plotted.
And
do
not
include
plotted
data
after
the
impact
with
the
wall.
g.
Add
and
label
a
dashed
line
to
the
graphs
showing
the
result
if
the
initial
velocity
of
the
man
were
+5
m/s.
(Note:
do
not
carry
this
procedure
out
on
the
simulation.)
h.
Describe
two
changes
that
occur
on
the
velocity
vs.
time
graph
each
time
you
make
the
initial
speed
of
the
man
greater.
Step
4:
Back
Up
the
Choo­Choo
a.
Clear
the
graphs.
The
acceleration
graph
is
still
hidden.
b.
Set
the
initial
position
of
the
man
to
0
m.
Set
the
initial
velocity
of
the
man
to
–2.0
m/s.
c.
Run
the
simulation
and
observe
the
motion
graphs.
Again,
the
motion
ends
when
Moving
Man
crashes
into
the
wall,
so
stop
the
simulation
when
that
happens.
Sketch
the
graphs
on
the
same
set
of
axes
used
for
Step
3,
disregarding
data
from
the
wall
impact
and
beyond.
d.
Clear
the
graphs.
Set
the
initial
velocity
of
the
man
to
–4.0
m/s
and
run
the
simulation.
Describe
two
differences
in
the
position
vs.
time
graph,
and
add
a
line
to
your
previous
sketch
representing
the
–4.0
m/s
motion.
Be
sure
to
label
both
lines
now
plotted.
e.
Add
and
label
a
dashed
line
to
the
graphs
showing
the
result
if
the
initial
velocity
of
the
man
were
–10
m/s.
(Note:
Do
not
carry
this
procedure
out
in
the
simulation.)
More curriculum can be found in Pearson Addison Wesley‘s Conceptual Physics Laboratory Manual:
Activities · Experiments · Demonstrations · Tech Labs by Paul G. Hewitt and Dean Baird. ISBN: 0321732480
f.
Describe
two
changes
that
occur
on
the
velocity
vs.
time
graph
each
time
you
make
the
initial
speed
of
the
man
greater
(faster
in
the
negative
direction).
g.
Click
the
on‐screen
button
to
show
the
acceleration
vs.
time
graph.
What
does
the
acceleration
vs.
time
graph
tell
you
about
the
motions
observed
so
far?
Step
5:
Pickin’
Up
the
Pace
a.
Clear
the
graphs.
All
three
graphs
are
now
showing.
b.
Set
the
initial
position
of
the
man
to
0
m.
Set
the
initial
velocity
of
the
man
to
0
m/s.
Set
the
acceleration
of
the
man
to
+0.5
m/s2.
c.
Run
the
simulation
and
observe
the
motion
graphs.
Sketch
the
graphs
on
the
graph
page.
d.
What
does
the
acceleration
vs.
time
graph
tell
you
about
the
nature
of
this
motion?
(Do
not
refer
to
numerical
values
in
your
response.)
Step
6:
Once
More,
With
Feeling
a.
Set
the
initial
position
of
the
man
to
0
m.
Set
the
initial
velocity
of
the
man
to
0
m/s.
Set
the
acceleration
to
the
man
to
+2.0
m/s2.
b.
Run
the
simulation
and
observe
the
position
vs.
time
graph.
i.
Sketch
the
graph
on
the
same
set
of
axes
as
part
5.
ii.
How
is
this
position
vs.
time
graph
different
from
the
one
plotted
in
part
5
above?
c.
How
does
the
velocity
vs.
time
graph
differ
from
the
one
produced
in
part
5
above?
d.
Based
on
what
you
learned
in
Steps
5
and
6,
sketch
all
three
motion
graphs
that
the
man
would
produce
if
he
started
at
x
=
0
m,
v
=
0
m/s,
and
a
=
–1
m/s2.
Don’t
actually
carry
this
procedure
out
on
the
simulation.
Simply
sketch
what
you
think
it
should
be
based
on
your
experience.
More curriculum can be found in Pearson Addison Wesley‘s Conceptual Physics Laboratory Manual:
Activities · Experiments · Demonstrations · Tech Labs by Paul G. Hewitt and Dean Baird. ISBN: 0321732480
Step
7:
Round
Trip
a.
With
all
three
graphs
showing,
adjust
the
scale
of
the
time
axis
to
display
20
seconds.
b.
Set
the
initial
position
of
the
man
to
–10
m.
Set
the
initial
velocity
to
+3.0
m/s.
Set
the
acceleration
to
–0.3m/s2.
c.
Run
the
simulation
and
observe
the
motion
graphs.
Sketch
the
graphs
on
the
graphs
page.
d.
Select
the
best
descriptions
of
the
velocity
and
acceleration
of
the
man
at
the
apex
of
his
motion
(when
he’s
is
farthest
from
his
starting
point).
Choose
one
description
of
the
man’s
velocity
and
one
description
of
the
man’s
acceleration.
Feel
free
to
use
the
rewind
and
forward
step
features
of
the
simulation.
__The velocity is positive: the man is moving to the right.
__The velocity is zero: the man is at rest.
__The velocity is negative: the man is moving to the left.
__The acceleration is positive: the man’s velocity is increasing.
__The acceleration is zero: the man is maintaining constant velocity.
__The acceleration is negative: the man’s velocity is decreasing.
e.
You
overhear
a
classmate
telling
someone
that
it’s
possible
for
an
object
to
be
at
rest
and
accelerating
at
the
same
time.
What
do
you
think
of
that
statement?
Step
8:
The
Sloshing
Man
Puzzle
a.
Clear
all
graphs.
Set
the
position
near
–2
m.
Click
and
drag
the
man
from
–2
m
to
+2
m
with
uniform
motion
and
let
him
rest.
Then
drag
him
from
+2
m
to
–2
m
with
uniform
motion
and
let
him
rest.
Repeat.
The
resulting
position
vs.
time
graph
should
look
similar
to
the
plot
below.
Don’t
worry
about
the
time
too
much;
what’s
important
is
moving
the
man
one
way,
then
resting,
then
moving
him
the
other
way,
then
resting.
Your
lines
won’t
be
as
straight,
and
the
“corners”
of
your
graph
will
be
rounder
than
those
depicted
below.
Figure 2. Ideal Position vs. Time for Sloshing Man
b.
Examine
the
section
of
the
plot
enclosed
in
the
dashed
box.
The
velocity
vs.
time
graph
has
a
pattern
similar
to
the
one
shown
below.
Unlike
the
time‐aligned
graphs
in
the
simulation,
this
graph
may
have
been
shifted
horizontally.
Draw
a
box
to
enclose
the
section
of
the
velocity
graph
that
corresponds
to
the
boxed
section
of
the
position
vs.
time
graph
above.
Figure 3. Ideal Velocity vs. Time Segment for Sloshing Man
More curriculum can be found in Pearson Addison Wesley‘s Conceptual Physics Laboratory Manual:
Activities · Experiments · Demonstrations · Tech Labs by Paul G. Hewitt and Dean Baird. ISBN: 0321732480
c.
The
acceleration
vs.
time
graph
has
a
pattern
similar
to
the
one
shown
below.
Again,
this
graph
may
have
been
shifted
along
the
time
axis.
And
it
is
not
necessarily
to
scale.
Draw
a
box
to
enclose
the
section
of
the
acceleration
graph
that
corresponds
to
the
boxed
section
of
the
position
vs.
time
graph
above.
Figure 4. Ideal Acceleration vs. Time Segment for Sloshing Man
d.
Sketch
the
velocity
and
acceleration
plots
in
the
space
below
the
position
plot
in
Figure
5
below.
Figure 5. Motion Graph Segment for Sloshing Man
e.
Match
the
phrases
below
to
the
motion
illustrated
in
Figure
5.
Use
points
A,
B,
C,
or
D,
or
segments
(e.g.,
AB,
BD).
Sustained positive velocity _______
Sustained negative velocity _______
Positive acceleration to start motion _______
Negative acceleration to start motion _______
Rest _______
Positive acceleration to stop motion _______
Negative acceleration to stop motion _______
More curriculum can be found in Pearson Addison Wesley‘s Conceptual Physics Laboratory Manual:
Activities · Experiments · Demonstrations · Tech Labs by Paul G. Hewitt and Dean Baird. ISBN: 0321732480
More curriculum can be found in Pearson Addison Wesley‘s Conceptual Physics Laboratory Manual:
Activities · Experiments · Demonstrations · Tech Labs by Paul G. Hewitt and Dean Baird. ISBN: 0321732480
More curriculum can be found in Pearson Addison Wesley‘s Conceptual Physics Laboratory Manual:
Activities · Experiments · Demonstrations · Tech Labs by Paul G. Hewitt and Dean Baird. ISBN: 0321732480