Find the value of the unknown resistance X in the circuit of fig if no current flows through the - Physics - Current Electricity

Question

Find the value of the unknown resistance X in the circuit of fig
if no current flows through the section AO Also calculate the
current drawn by the circuit from the battery of emf 6 V and
negligible internal resistance

Debalina Deb · Accepted Answer

Dear student,

Given Data:

R1 = 2 ohm

R2 = 4 ohm

R3 = 3 ohm

Now, R1 / R2 = R3 / Y

Y = R3 x R2 / R1

By putting the values in above equation:

Y = 3 x 4 / 2

Y = 6 ohms

Ra = 6 ohms

Rb = 3 + 6 = 9 ohms

As Ra and Rb are anti-parallel

1/ Ro = 1/6 + 1/9

1/ Ro = 3 + 2/18

Ro = 18/5 = 3 6 ohms

R = 3 6 + 2 4 = 6 ohms

The resistance of an unknown resistance will be 6 ohms

And current =6V/6 ohm =1 Amp (using Ohms law)

Regards,

Find the value of the unknown resistance X in the circuit of fig. if no current flows through the section AO. Also calculate the current drawn by the circuit from the battery of emf 6 V and negligible internal resistance