Question

Tje galvanometer shows no deflection. What is the resistance x ​

Answer 1

Consider the closed loop. BCDB

2(2.1−Ig)−5(I2+Ig)−RIg=02(2.1−Ig)−5(I2+Ig)−RIg=0

At null deflection Ig=0Ig=0

Hence 2(2.1)−5I2=02(2.1)−5I2=0

4.2−5I2=04.2−5I2=0

=> I2=4.25I2=4.25=0.84A=0.84A

Hence the current through the 5Ω5Ω resistance is 0.84A