Question

In the network resistors each of value R shown in
the fig., calculate the equivalent resistance between
the junctions A and E:-
(1) 12 R
(2) 7R/12
(3) 12R/7
(4) R/12​

Answer 1

Answer:

If we connect a battery across A and B, then E and D will be at the same potential and F and C will be at the same potential. Then the equivalent is as shown in figure.

here, R  

eq1

​  

=R∣∣2R∣∣R=(1/R+1/2R+1/R) ^-1

=(2R/5)

Thus, equivalent resistance A and B is RAB  

=R∣∣(R/2+2R/5+R/2)=R∣∣(7R/5)=  

R+7R/5 /R(7R/5)​  

=  

7R/12

​