68
G
ETTING
S
TARTED WITH THE
CBL 2™ S
YSTEM
© 2000, 2003 T
EXAS
I
NSTRUMENTS
I
NCORPORATED
8.
The lemon produced the highest voltage. Other factors to consider: least messy
(ease of use), lowest cost, and so forth. You may also want to discuss which
battery is the “best”: the battery with the highest voltage or the battery that
maintains its voltage the longest (a slower rate of change).
9.
10.
the voltage drops
11.
y = ax + b, a =
.
4.2E-5, b = 0.7
12.
A
represents the rate at which the voltage is dropping. The value of
B
is the
y-intercept. This should be close to the voltage at the beginning of the long-
term experiment.
13.
.73 - .52 = .21 volts
14.
16,667 seconds (4 hours, 38 minutes)
15.
No, it does not. The original data taken shown that the voltage had leveled off
at about .5 volts at 1.5 hours and stayed there.
16.
The fruit chosen, the electrolyte (juice) of the fruit drying up, the penny and
washer getting “dirty” or tarnished over time
Reference
Data Collection Activities for the Middle Grades with the TI-73, CBL and
CBR:
Young and Johnston; Activity 12: You’ll Get a Charge Out of This!; TI
Explorations™ Book.