Equivalent resistance?

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1 Answer
Mar 17, 2018

#C#

Explanation:

You can think this way,

Let,equivalent resistance of the whole circuit between point #A# and #B# is #R# when, the link is not present.

If the link of #1 Omega# was present,it would have in parallel to #R#

So,equivalent resistance between #A# and #B# would have been #(R×1)/(R+1)#

Which is given to be #7/12 Omega#

So, #(R×1)/(R+1) =7/12#

Or, #12R =7R +7#

So, #5R=7#

Or, #R=7/5 Omega#