A resistance wire connected in the left gap of a metre bridge balances a $10 \Omega$ resistance in t

Question

A resistance wire connected in the left gap of a metre bridge balances a $10 \Omega$ resistance in the right gap at a point which divides the bridge wire in the ratio $3: 2$. If the length of the resistance wire is 1.5 m , then the length of $1 \Omega$ of the resistance wire is\

Professor PC Thomas Classes · Answer

(b) : Unknown is $X, R=10 \Omega$. Here, $\frac{l_{1}}{l_{2}}=\frac{3}{2} ; \frac{X}{R}=\frac{l_{1}}{l_{2}}$\ $\Rightarrow X=\frac{3}{2} 	imes 10 \Rightarrow X=15 \Omega$\ Thus, 1.5 m length has resistance $15 \Omega$ hence, length of $1 \Omega$ of the resistance wire $=\frac{1.5}{15}=0.1 \mathrm{~m}=1.0 	imes 10^{-1} \mathrm{~m}$\