Calculating the Resistance of a Wedge

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    Resistance Wedge
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The discussion focuses on calculating the resistance of a wedge-shaped object using the formula R=ρ (L/(T*W)), where L is the length and T*W is the cross-sectional area. Participants suggest that using an integral is necessary for accurate calculations due to the wedge's geometry. They recommend introducing a variable for the distance from one end of the wedge and measuring resistance with an ohmmeter at specific points. The conversation highlights potential complications at the wedge's tip, which may affect the resistance calculation. Overall, the consensus is that an integral approach is essential for this type of geometry.
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I'm interested in calculating the resistance of an object using the formula:

R=ρ (L/(T*W)) where L is the length and T*W is the cross sectional area.

My object is however, a wedge, so I do not know exactly how to calculate the resistance without doing an integral:

http://imageshack.us/photo/my-images/585/9evf.jpg/

Is this the proper approach? I'm having some trouble with the actual calculation of this... not sure if I'm setting up the problem correctly. Any help would be much appreciated!
 
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elionix said:
I'm interested in calculating the resistance of an object using the formula:

R=ρ (L/(T*W)) where L is the length and T*W is the cross sectional area.

My object is however, a wedge, so I do not know exactly how to calculate the resistance without doing an integral:

http://imageshack.us/photo/my-images/585/9evf.jpg/

Is this the proper approach? I'm having some trouble with the actual calculation of this... not sure if I'm setting up the problem correctly. Any help would be much appreciated!
Doing an integral is how I would calculate it. Is there some reason you do not want to use an integral?
 
It's not entirely clear which way you have wi and li. I assume it's intended to be consistent with l being the distance from wedge base to tip.
blocks have dw, dl dimensions
dl, yes, not dw.
You need to introduce a variable for the distance of an element from one end. I suggest taking it from the tip end and using x. (So an element thickness is dx, not dl.) What is w as a function of x?
 
If you were measuring the resistance with an ohmmeter where would you touch the probes? At the tip and the center of the left base? I assume that there is no metal plate along the left edge, yes?
 
barryj said:
If you were measuring the resistance with an ohmmeter where would you touch the probes? At the tip and the center of the left base? I assume that there is no metal plate along the left edge, yes?
Well, I assumed the contact at the wide end was right across. However, there is a problem at the pointy end, as will be revealed by the integral.
 
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