Class 12 NEET Physics Current Electricity Questions Part 1

By symmetry, currents i1 and i2 from A is the same as i1 and i2 reaching B As the same current is flowing from A to O and O to B,O can be treated as detached from AB Now CO and OD will be in series hence its total resistance =2Ω
It is in parallel with CD so equivalent resistance
=

2×1

2+1

=

2

3

Ω
This equivalent resistance is in series with AC and DB. So total resistance =

2

3

+1+1=

8

3

Ω
Now

8

3

Ω is parallel to AB that is 2Ω. So total resistance
=

( 8 3 )×2

( 8 3 )+2

=

16 3

14 3

=

16

14

=

8

7

Ω