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 ...
The testing program for this experiment is summarized in Table 1
Table 1. Testing Program
Test ID
|
Wire Diameter (cm)
|
Wire Material
|
Wire Length (cm)
|
Run #1
|
0.19
|
Steel
|
30.6
|
Run #2
|
0.19
|
Steel
|
15.5
|
Run #3
|
0.10
|
Steel
|
30.6
|
Run #4
|
0.10
|
Steel
|
15.5
|
Run #5
|
0.14
|
Brass
|
30.6
|
Run #6
|
0.14
|
Brass
|
15.6
|
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)
This example does not directly apply to what you tested. The takeaway from this example is:
1. Use linetype or color to help visually distinguish data
2. Label slope values, "k = ..."
3. Don't forget to normalize!
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
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2
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3
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4
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5
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6
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† cite source
* % diff = (measured - expected)/expected
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.
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 ...
Attachment:- Assignment.rar