Thursday, Feb 12, 2009 - Block 3

Collected Oleic Acid Lab write-ups

Handed out IB Internal Assessment Guidelines and went over the Design, Data Collection and Presentation, and Results sections.

Went over spring constant lab. Asked students how they might approach it.
Instead of using a stopwatch and ruler, students will use the Vernier Motion Detector.

Explained how to collect the data for both the static and dynamic methods.

This lab will concentrate on the Data Collection and Presentation, and Results parts of the IB Internal Assessment.
Lab write-up
Static Method: I want a brief description of how students collected the data.
Show data tables complete with headers and labels.
Use Excel to create a graph
Use the Linest function to determine the uncertainty in the slope.

In the calculations section, explain and give a sample calculation for each type of calculation. Explain how you get the various quantities.

Dynamic Method: Again give a brief description of how you collected the data.
Show data tables complete with headers and labels.
Figure out what to graph to get a linear relationship
Use Excel to create a graph but this time do not force the line to go through the origin. Find the x-intercept which gives the correction factor for the mass of the spring.
Use linest to find the slope, uncertainty in slope, y-intercept, and uncertainty in y-intercept.
Determine the spring constant and its uncertainty.

Calculation section - explain and give a sample calculation for each type of calculation. Explain how you get the various quantities.

In the results section, clearly state the results along with their uncertainties. Compare and comment on the two methods. Discuss weaknesses in the two methods. Describe ways in which the procedure could be improved.

Determine the effective spring constants for combinations of springs and describe the method used to do this.

Answer the questions at the end of the lab explaining in your answer what it is you are answering.

Students worked in groups of two.

There was only one spring per group so they had to share for Part 3 of the lab.
Not all lap-tops had Logger Pro 3.5 on them

Students did not finish so I told them they could finish tomorrow.

I collected RA 11.1