Data and calculations, Questions – PASCO TD-8555 THERMAL RADIATION SYSTEM User Manual
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Thermal Radiation System
012-04695D
ä IMPORTANT: Make each reading quickly, removing the heat shield only as long as it
takes to make the measurement. Take care that the position of the sensor with respect to the
cube is the same for all measurements.
⑥ Replace the heat shield, and turn the cube power to 10. When the temperature has risen an
additional 12-15 C°, repeat the measurements of step 5. Repeat this procedure at about 12-15°
intervals until the maximum temperature of the cube is reached.
Data and Calculations
Room Temperature:
R
rm
= ________
Ω
T
rm
= ____ °C = _____ K
① Using the table on the base of the Thermal Radiation Cube, determine T
c
,
the temperature in
degrees Centigrade corresponding to each of your thermistor resistance measurements. For
each value of T
c
, determine T
k
, the corresponding value in degrees Kelvin (K = °C + 273).
Enter both sets of values in Table 4.1, above. In the same manner, determine the room tem-
perature, T
rm
.
② CalculateT
k
4
for each value of T
k
and record the values in the table.
③ Calculate T
k
4
- T
rm
4
for each value of T
k
and record your results in the table.
④ On separate sheet of paper, construct a graph of Rad versus T
k
4
- T
rm
4
. Use Rad as the depen-
dent variable (y-axis).
Questions
① What does your graph indicate about the Stefan-Boltzmann law at low temperatures?
② Is your graph a straight line? Discuss any deviations that exist.
R
Rad
T
c
T
k
T
k
4
T
k
4
- T
rm
4
( ý )
(mV)
(°C)
(K)
(K
4
)
(K
4
)
Data
Calculations
Table 4.1