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30
G
ETTING
S
TARTED WITH THE
CBR 2™
S
ONIC
M
OTION
D
ETECTOR
©
1997,
2004,
2006
T
EXAS
I
NSTRUMENTS
I
NCORPORATED
Activity 5—Rolling Ball
(cont.)
Parabolic
g. Select Next (press
q
) to display a summary of the new
settings.
h. Select OK (press
s
) to return to the main screen.
Í
When the settings are correct, choose Start (press
q
) to begin sampling.
Î
When the clicking begins, release the ball immediately (don’t push) and step back.
Ï
When the clicking stops, the collected data is transferred to the calculator and a plot of
distance vs. time is displayed.
Answer questions 2, 3, 4, and 5.
Explorations
Examine what happens for differing inclines.
Ê
Predict what will happen if the incline increases.
Answer question 6.
Ë
Adjust the incline to 30
¡
. Repeat steps 2 through 6.
Add this plot to the drawing in
question 6, labeled
30
¡
.
Ì
Repeat steps 2 through 6 for inclines of 45
¡
and 60
¡
and add to the drawing.
Í
Answer question 7.
Advanced explorations
Adjust the time values so that x = 0 for the initial height (the time at which the ball was
released. You can do this manually by subtracting the x value for the first point from all the
points on your plot, or you can enter
L1(1)
"
A:L1
N
A
"
L1
.
Ê
Calculate the values for
a
,
b
, and
c
for the family of curves in the form
y = ax
2
+ bx + c
at 0
¡
, 15
¡
, 30
¡
, 45
¡
, 60
¡
, 90
¡
.
Ë
What are the minimum and maximum values for
a
? Why?
Ì
Write an expression describing the mathematical relationship between
a
and the angle
of inclination.