AIIMS 2017 Physics Question Paper for free online practice with solutions

The equivalent circuit is shown in fig. Since the Wheatstone’s bridge is balanced, therefore no current will flow through the arm KL. Equivalent resistance between
AKM=R+R=2
Equivalent resistance between ALM=R+R
equivalent resistance between A and B is given

1

R

=

1

2R

+

1

2R

2

2R

=

1

R

i.e.,R'=R