# Calculation of effective resistance [closed]

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Six resistors are arranged along the edges of a pyramid as shown below. The values of the resistances are shown in the figure.

How can I find the effective resistance between A and B?

closed with the note: No Effort.
asked Nov 1, 2016
reshown Nov 2, 2016
You could try applying Kirchhoff's Rules.
Alternatively, redraw the diagram in 2D as a triangle (ABC) with central point (D), with resistors connecting each pair of points. The resistors around the central point D form a Y or 'star' shape. This can be turned into an equivalent 'delta' $\Delta$ shape using the $Y-\Delta$ or 'star-delta' transform (look  it up). This leaves you with inner and outer triangles, each side being parallel resistors, which is easily reduced further and solved.
This question looks to me as a objective type question which is to be solved within 3-4 minutes.so star delta transform but would be too lengthy  and time consuming.instead this question can be solved by using symmetry .points D and C are equipotential points so we can removed the branch CD which then becomes simple series and parallel combination of resistances.
@sammygerbil would you consider removing the closed status.I think this is a good question.Thanks.
Sorry, I don't have moderator status so I cannot reopen questions. I do not think the Moderator (Einstein) will reopen unless Swapnil Das shows some effort.

Yes I think you are correct : nodes C and D are symmetrical wrt AB, so the link CD carries no current and can be removed.