Question

In the circuit shown, a metre bridge is in its balanced state. The metre bridge wire has a resistance 0.1 ohm/cm. The value of unknown resistance X and the current drawn from the battery of negligible resistance are ____________.

Options

• `6  Omega  5` A

• `10  Omega,  0.1` A

• `4  Omega  1.0` A

• `12  Omega  0.5` A

Answer 1

In the circuit shown, a metre bridge is in its balanced state. The metre bridge wire has a resistance 0.1 ohm/cm. The value of unknown resistance X and the current drawn from the battery of negligible resistance are `4  Omega  1.0` A.

Explanation:

Resistance of the part AC,

`"R"_"AC" = 0.1 xx 40 = 4Omega`

`"and R"_"CB" = 0.1 xx 60 = 6Omega`

`"In balanced condition,"  "X"/6 = 4/6 Rightarrow "X" = 4Omega`

`"Equivalent resistance R"_"eq"=5Omega   "so current drawn from battery"  "I" = 5/5 = 1A`