Q. In the figure, the potentiometer wire AB of length L and resistance 9r is joined to the cell D of emf ε and Internal resistance r. The cell C"s emf id  ε /2 and its internal resistance is 2r. The galvanometer G will show no deflection when the length AJ is:- 



a. 4L/9
b. 5L/9
c. 7L/18
d. 11L/18

Dear Student,
                           let at x distance it will so no deflection then current on AB=ε10rin case of no deflection 9rL×(x)×ε10r=ε29εx10L=ε2x=5L9
Regards

  • 32
What are you looking for?