The effective resistance between terminals A and B in the

Home » Network Theory » Network theory miscellaneous » Question

The effective resistance between terminals A and B in the circuit shown below is—

1. R
2. R – 1
3. R/2
4. 6 R
  11

Correct Option: C

The given circuit:

By converting star network into delta network

R_{eq. (AB)} = R_AB || (R_AC + R_BC)
Where,
R_AB = R || 3R = 3/4 R
R_AC = R || 3R = 3/4 R
R_BC = R || 3R = 3/4 R
Now,

R_{eq. (AB)} =	3R		3R	+	3	R
	4		4		4

=	3R		6	R =	3R/4 × 6R/4
	4		4		3R/4 + 6R/4

=	18R²	=	R
	16 × (9R/4)		2

Hence alternative (C) is the correct choice.