Paper details:Lab 3: Torsional Behavior of Metals
Lab Section (e.g. A, B, C, etc…)
Term: (e.g. Spring 2015)
Your Name: (e.g. John Smith, Jane Smith)
1 ABSTRACT (5 PT.)
The objective of this experiment was the find the relationship between the applied torque and angle of twist for a metal wire of various (lengths, diameters, and/or materials); and compare and contrast with each other. This was accomplished by … … The findings were … … Based on the findings, the author concluded that …
2 RESULTS (65 PT.)
The testing program for this experiment is summarized in Table 1
Table 1. Testing Program
Test ID Wire Diameter Wire Material Wire Length
Run #1
Run #2
Run #3
Run #4
Run #5
Run #6

The influence of Diameter, Length and Modulus on Rotational Stiffness is shown in Figures 1 through 3, respectively.

Figure 1. Influence of Diameter on Rotational Stiffness (TL/G versus Angle of Twist)
Insert Figure 2 here
Figure 2. Influence of Length on Rotational Stiffness (T/JG versus Angle of Twist)
Insert Figure 3 here
Figure 3. Influence of Shear Modulus on Rotational Stiffness (TL/J versus Angle of Twist)

Table 2 summarizes the above results.
Table 2. Summary of Results
Run Dia., D Length, L Material Expected Shear Modulus, G† Rotational Stiffness, K % diff*
measured expected
1
2
3
4
5
6
† cite source
* % diff = (measured – expected)/expected
3 DISCUSSION OF RESULTS (20 PT.)
1. Why did you normalize the above graphs? What is the significance of the resulting slopes?

2. Define “rotational stiffness” in terms of a member’s geometric and material properties.

3. How do the experimental measurements compare with expected values? Explain the cause/significance of the similarities/differences – be specific and do not blame “human error”.

4. Explain how modulus of rigidity, G, is analogous to modulus of elasticity, E.
4 CONCLUSIONS (10 PT.)
The original objective of this experiment was to find the relationship between the applied torque and angle of twist for a metal wire of various (lengths, diameters, and/or materials); and compare and contrast with each other. Based on the above results, the author determined that …