In the circuit a meter bridge a shown in the balanced state .The meter bridge wire has a resistance of `1 Omega //cm`. Calculate the unknown resistance `Y` and the current drawn from the battery of negiligible internal resistance

Answer

` 0.66 A`

Explanation

When is balance no current flow throgh galvameter so
`(X)/(6) = (40)/(60) = (2)/(3) or X = (2)/(3) xx 6 = 4 Omega `
Total resistance of bridgh wire `AB = 1 xx 100 = 100 Omega`
Total resistance of resistance `X (= 4 Omega and 6 Omega` connected in series `= 4 + 6 = 10 Omega `
The resistance is in parallel with the resistance of wire `AB`
Effective resistance of circuit
`R = (10 xx 100)/(10 + 100) = (100)/(11) Omega`
current draw from the battery
`I = (6)/(100//11) = 0.66 A`