PASCO ET-8781 Equivalent of Heat Tube - Manual (Page 7)

Mechanical Equivalent of Heat Tube Model No. ET-8781
6 ®
Suggested Experiment
Exploring Energy Changes During the Rotation of a Heating Tube
Equipment required: Mechanical Equivalent of Heat Tube (ET-8781), DataStudio software,
computer interface (PASPORT or ScienceWorkshop), Temperature Sensor
Note: The Heat Tube must be used with a Temperature Sensor that accepts a stereo plug input
(i.e. PS-2125 Temperature Sensor, PS-2143 Quad Temp. Sensor, PS-2146 Absolute Pressure/
Temp. Sensor, or CI-6527A Thermistor Sensor)
1. Connect the Heat Tube to a Temperature Sensor and computer interface (For instructions, see
steps 1 and 2 under “Equipment Setup.”)
2. Launch DataStudio. In DataStudio’s Experiment Setup window, set the sample rate to as
fast as possible. In the Data list, double click on the Temperature icon to open the Data
Properties dialog. In the Data Properties dialog, set the accuracy to 0.01 and the precision
to 2. Click the OK button.
3. Pull off the cap on the heating tube. Weigh the mass of enough steel balls to cover one
layer on the surface of the aluminum plate on the inside of the tube.
4. Remove the aluminum plate from the plastic cap. Weigh the plate.
5. Put the balls in the tube. Reinsert the aluminum plate and push the cap back tight on the
tube.
6. Measure and record the length of the tube.
7. In DataStudio, open a Graph display and click the Start button. Hold the Heat Tube
upright in a vertical position with the cord end at the bottom. Hold the tube in the center
with your hands over the Velcro strap. Keep your hand at the level on the tube. Turn the
tube upside down and back up. Watch the temperature change in DataStudio.
8. Rotate the tube back and forth three times. Record the biggest change in the temperature.
(Note: To record the change, use the Smart Tool. In the Graph display, click on the Smart
Tool button. Hover the pointer over the box until the pointer becomes two double-headed
arrows. Drag the arrows to the desired location. The x and y coordinates appear to the right
of the arrows.
9. Calculate the loss in gravitational potential energy for one back and forth motion. Use
equation 1 for the calculation.
10. Calculate the increase in thermal energy of the balls and plates for the largest
temperature change, , using equation 2.
∆T